I'm scared

Okay so I've been seeing this guy just over a month now. At first it just seemed like fun and we enjoyed each other's company. He's a friend of my ex's, my ex who was horrible to me after I dumped him. Anyway things were okay up until yesterday, when it suddenly just clicked. I realised how much I really liked the guy. I've only ever had a proper crush on a guy once and by the time I realised I had already messed it up. It hurt so so much, most intense emotional pain I had felt. Anyway so this guy has said he likes me but has been distant on text. Now I'm not a big texter myself but he really didn't seem to have any interest in me and as a teenager in today's society, texting means something. Other things have come into play and I'm getting mixed signals. Also yesterday we were gonna have sex but he didn't exactly...get hard. Really embarrassing for me and he wasn't exactly reassuring that it wasn't my fault, so part of me thinks it is. I am trying to plan it cool but really I am so fricking scared if it all messes up. I know the advice I will be given is probably to relax and let things happen, I will do that but I guess I need some support and reassurance.