He couldn't get hard...?

Sooo after an amazing first date last weekend & texting/snapping all week, I went on a second date with this guy and we ended up going back to his place to hook up. After he went down on me we started to fuck - when we tried to change positions he got soft and couldn't get hard again. I tried sucking him off but that didn't work..... after spending the night with him he seemed really embarrassed and like I genuinely believe that it wasn't bc he's not attracted to me but does anyone have any insight into situations like this? Like it sucked and made me feel self conscious lol