Bad first time?

So my boyfriend of a year and I finally tried to have sex today, we're long distance so we really don't get to see eachother too often. We're both 17 and I was his first everything, so he's pretty inexperienced. I put the condom on for him and everything and first we tried missionary but he couldn't get his penis in even though we tried at least 20 times. I would show him where to put it and it would kind of just slide around and wouldn't go in. I tried guiding it in too but I couldn't get it in. Then I tried to ride him instead, and we still couldn't get it in. I was relaxed so it wasn't a matter of being tense, I'm a regular tampon user and can easily insert my own fingers. I could care less really (even though I'm a little sad because I was excited) but I'm pretty sure he's embarrassed. Has this ever happened to anyone else? How did you finally get it in?