Am I going insane...

I am 7 weeks pp, and i feel my emotional side of me is actual going insane, i am extremely angry all the time and for the first time since before i was pregnant i just started crying because my son won't go back to sleep. My son is the fussiest baby i've ever met in my life, he has reflux, colic and just cries every time he is awake. He's is on medication for both of them. I am seriously not enjoying my experience being a mum because i cant play or talk with him without him screaming his head off. He never lets me sleep and i feel i am going insane. I'm physically and mentally drained right now, i can't bare the sound of my son crying anymore. I actually screamed at my partner the other day and said i was going to run away and leave him with my son. I feel like such a failed mum, how could i think such a thing. Am i going insane???