I need help with orgasms

I used to be able to concentrate and orgasm while my SO is inside of me. Its also known as vaginal stimulation i think. But i used to orgasm while he was inside of me. But i havent for weeks. And it doesnt take much for trying. But ive been trying hard like crazy....expecially tonight. I literally burst into tears cause i could orgasm. Anyone want to share if you've experienced the same thing?