First of all, I'm about 5'6", and about 155lbs and I have a descent build, and I keep in shape by working out. I'd like to consider myself above average looking. I've never had a problem with my height. As long as you don't let it become a problem within yourself, your fine. If someone else has a problem with your height, then that's their problem not yours. Just be happy with yourself.
As for picking up girls. Just this weekend I was at a bar, and I was with my taller friend who's about 6'1". He's a great DJ, and I've sharpened up my skills really good aswell (I acutally learned a lot of skills from him). I came out on top that night with picking up more women then him. Most of the women were taller then me. I even witnessed a significant taller girl reject him, and give me her number. Most nights at a bar I have no problem picking up women, taller or shorter, it has a lot to do with my style and my confidence at the club. I carry that same style and confidence at college, gym whereever I can.
I had three LTR hb ex-girlfriends in the past that were taller then me. They had no problem with it. Obviously some girls will not like you because your shorter, just as some girls might not like you because of your race/religion/skin color etc... these are factors beyond your control and therefore you shouldn't let them be a significant factor in how you shape your life and your djing skills. Polish up your other skills, and don't let it bother you. Get over your height issure if your insecure about it, infact try to get rid of all your insecurities. The hb I am with now is about 1-2 inches shorter then me barefoot and the same height or a bit taller wearing heels. For me this is perfect.
Another tip: I think David DeAngelo was saying if your shorter then the girl, the mind set and message you should convey in a ****+ funny manner is that normally you won't even consider dating a taller girl but you might make it an exception this time. This is sort of turning the tables on them for being taller then you.
Keep Pimpin'
-MasterPlayer