What do I do?

My boyfriend and I where having a conversation the oher night, I happened to ask him hif he goes out on boys nights, if any girls approach him what does he talk about. the thing that concerned me was that he asks there name which is fine but the thing I am a little weary about is that he asks them where they live. Now normally if a guy asks a girl where they live when your out on the town to me it means they want to sleep with you. Am I being silly or should I be worried? Also I am I sometimes check his mobile for txt msg and find sometimes when he recieves/sends he will delete them after, that is also worrying medoes he have something to hide? Please advise, he always says he would never cheat on me, but I dont know.