Been there. It was horrible and I felt soooooooo jealous of other mums who had angelic, smiling, quite babies.
With DD1, it went on until she was 14 months old, worse at night. I took her to the GP a number of time, but I was labelled an anxious mum, said she had colic (at more than 6 months!) and refused to listen. In the end, it turned out that she had problems digesting fibre and suffered with horrible cramps. Poor thing. It did stop me sometimes feeling like i wanted to throw her on the other side of the room, but knew that I would never ever do it, just getting the thoughts in my mind.
DS suffered from horrendous colic until he was 5 months old and cried cried cried. Horrible again.
What I can say though is that when friends experienced their angelic babies turned into horrible toddlers, it was my time to smile because my two turned into very easy toddlers, easy kids, and all in all easy teenagers, so the compromise was fair enough!
Good luck OP, hope it gets better very soon.