Help! Advice

So my bf and I have been talking for at least 6 months and dating for 1 month now. He's great and all but lately he's been really short with me and he barely texts me during the day, when he used to text me all the time. He always is playing around when I'm trying to have a serious convo with him and it's just really irritating sometimes. When we actually do talk it's almost always something sexual too..I don't know if it's just me over reacting about ever little thing, or if I should say something to him about it.