I have this exact same problem and I can sometimes notice that someone may like me, but I never know if it's enough to ask them out. I've always been a little on the shyer side and don't want to emberace myself by being rejected. I don't want to end any freindships with people either by being rejected. I feel that this may happen and I don't know who I should ask out and who I shouldn't.
-I have never asked anyone out and i'm 15. I'll ive ever done was dance or just flirt with girls a bit, but mostly at camp, which everyone does. At camp its different, lol.