Not comfortable having sex

A while back, 2 weeks ago I think, I made a post saying that I freaked out when my fiancé and I tried to have sex. I think I know what set me off but I'm still not sure why it did. However, Since then, I e been having trouble getting intimate again. I haven't really been able to get turned on because everytime I start to feel turned on I make him stop because the feeling freaks me out. Anything that would normally turn me on or any sexual touching makes me want to stop and move away. I don't know why this is happening. He has never pushed sex on me, it's always consensual and I've never been abused or forced into sex in anyway that I can remember. Any advice for getting past this?