Can a Drill sergeant search you and only you without permission?

So, what you're saying is that your DS caught you doing what you weren't supposed to do, apparently more than once based on your comment about not being used to the freedom? On top of that, you believe that your DS is like a police officer who can only search her barracks (the ones you're staying in, and she's responsible for keeping safe and clean) when there's legal probable cause?
It sounds like you've been talking to the barracks lawyers too much.
You got caught doing what you weren't supposed to do. Then you made yourself a target and confirmed your DS' suspicions by becoming a repeat offender. All you've managed to do is confirm to your leadership that you are not capable of maintaining the same level of discipline and standards as your peers. There's an old saying in the Army, "90% of your time is taken up by dealing with 10% of your Soldiers". You've identified yourself early on as the repeat offender 10%.

If you can't take it, feel free to go talk to the 1SG. Tell them how you did, in fact break the rules, but it's not fair that you were targeted because.... Reasons.... I'm sure that 1SG will condone your actions with a complimentary Article 15 so that you feel more fairly treated.

Also, you're writing in English, your job will soon be to write memos and correspondence to commanders, XOs, and other officers. Learn how to use punctuation and write correctly.

I'm going to go with the premise that you are a young troop, new to the Army, looking for legitimate advice and not sharpshooting from the internet mob.
If you think you were done wrong in this situation, there is a chain-of-command for that. There are also outside CoC forms of redress, such as the IG, but I would caution you to use the CoC first.
Yes, by regulation the DS can toss your locker. He/she does not need probable cause, as your living space and everything in it are inspectable items at any time. Not that it matters, since the DI DID have probable cause since you had previous infractions. Turns out, their suspicions were correct. You might want to ask yourself how the DS found out about you having a phone. Hint: not everyone in your platoon likes you.
Having said that...
If you can't take it for two months, the Army is not for you. We tell you to do things you don't want to do; even dangerous things that might cause you bodily harm or death. We have rules you are expected to follow, and if you don't your property might get confiscated. You might even find yourself getting called on the carpet to explain yourself, but not really since it is a one way conversation, where an authority figure will chew you out for not following orders and take away your money, your rank, maybe even your job.

Look. I have been doing this for 26 years, and I figured a couple things out. If you show up in my formation, I don't know you from Adam at first, except insofar as you get there on time and in the right uniform. Troops on the radar are there because they did something to get on the radar. Do what you are told, get there on time, and be ready to train and we will get along smashingly. Get in my crosshairs by doing the wrong thing, try to barracks lawyer me, and break rules blatantly and repeatedly and we will not get along. It will go poorly for you, because I have lots of stripes and you do not.
It has nothing to do with "liking" you or not. It has everything to do with are you a disciplined member of a team that I can depend upon in combat or not.

My advice is simple. Shut up, ruck up, and follow the rules. You only have to manage that for two more months and you graduate and move on in your Army life. Then you get a fresh start with someone that you are not on the radar for and you can be the Soldier that we all want in our team.

For the love of Christ, know that your internet comments are seen by all, and live on long after this storm blows over. There is a fair to middling chance that your Social Media is being monitored, so do not incriminate yourself further by showing your ass to the world in a quest for support/ sympathy. All the internet support in the world and likes on facebook plus a bag of potato chips gets you a bag of potato chips and an Article 15.
Your post above also makes it abundantly clear that you did not learn your lesson and used yet another banned cell phone to post to RP. I would reconsider my priorities, if I were you.

You can listen to me or not. After all, I'm old and just don't understand the hell that is AIT these days. Most comments you will get on this thread will be more blunt, maybe even hostile and unhelpful. I am really trying to help you, if you will take the time to read, heed, and make the adjustment.
Good luck, PVT (Join to see) . I hope you figure out what will be your best path forward.

You should definitely report this to the 1SG, especially tell the 1SG you kept a phone you were required to turn in.
Keep your room squared away, and go back and read up a bit on Army Values and the UCMJ.
Your DS doesn't hate your or anyone else. It's likely your behavior, such as not keeping your room clean, and disobeying a lawful order. This behavior would lead an experienced DS to believe there is other behavior. This behavior goes against good order and discipline.