confused...

Im really confused. So I was on birth control after I had my baby. Got off it in September. The other night my boyfriend of 6 years and I had amazing sex. Normally takes me a while to get in the mood or just tell him no. We were both in the shower getting clean from the first go around. We got cought up in the moment again when he was washing me he got so hard and slid inside me. Caching me off guard and was speading up making me moan so much. My legs felt weak. Was After we were done I felt light headed and dizzy and needed to sit down. I felt amazing!! After that time in the shower I couldnt get back to normal which is not a bad thing. I seem to want him all the time. So much he is now telling me no... he asked if I was pregnant. And if I was ok. Because it is not normal for me. What im trying to ask is. Why am I all of a sudden horny all the time now??