Fussy 7 week old!!

My son is 6 weeks and 4 days and it seems like he cries all the time- he isn't smiling he doesn't really wanna be awake and when he is he's crying... He also doesn't sleep more than 21/2 hours.. I've taken him to the pedi and everything checks out so why the hell is my baby so freaking miserable?! I am breastfeeding and I don't eat much dairy, I don't eat spicy things or certain veggies like broccoli I just don't know what to do and when he will just be smiley and happy;(