I think you really need to stop worrying.. talk about anything and everything, be stupid. I'm like *the* most clumsiest and stupidist (if thats a word) person around my boyfriend. I'll knock stuff over, I bash him alot lol not on purpose but like I'll head butt him or step on his feet.. thankfully he laughs about it >.<

I think if you ever feel nervous or shy around him, just find something funny, laughter is the best cure for that in my opinion, laugh about it and get over it. However, if in the end, you two just don't have that much in common and you're really stuck for conversation topics maybe you need to think about where the relationship is headed and if you two are really suited.