Can I get age waiver to join the military @ 40?

I am neither a medical doctor nor a Chaplain. I missed the opportunity to join after completing all the process at MEPS when my mum was told I was joining the military reserve. She was scared for me. By the time I could persuade her, I already turned 40. There could be an exception to any rule. If it is possible, can someone please tell me how I can proceed with this? Thanks