This is quite embarrassing for me to ask so I'm asking here.. im very nervous about going to my doctor as it is so intimate!!

I was sleeping, when my partner woke me and began to kiss me. We then began to have sex, but I could not understand what we were doing. It was like my brain had completely glitched, I suddenly had no idea what sexual intercourse was and felt I had no idea on what to do. I enjoyed it, it felt good... but I couldn't understand what was happening or how long it was going to last etc..
When we stopped.. I went to the bathroom and I still felt that way while cleaning up for 5-10 minutes or so.
After, I began to cry because it scared me so much, I couldn't explain to him what had just happened and he said maybe I was just still asleep.

I have never experienced anything like this, I'm almost 30 and it really scared me!!!

Should I be concerned? Or is my anxiety playing up and I should forget it?

Thanks in advance