My first child had colic for 8 full weeks. It was absolutely one of the most horrible things I've ever been through. I was so sleep deprived that I even hallucinated one day; a separate time, while napping w/ him in my bed (& desperately trying to catch up on sleep), I wasn't awoken until he started crying b/c he was wedged b/twn the dresser and bed. I felt like such a horrible mother, so incompetent and overwhelmed.
We went through multiple medications & upright sleeping for our kid, thinking it might be GERD (reflux). We tried putting simethicone in his bottles to alleviate gas, in case that was the problem. Of course no one knows what causes colic, so it was a frustrating search for anything that would work.
We tried using only formula, and different kinds of formula, since breastfeeding didn't calm him down. I tried doing both breastfeeding & formula, different combinations. I wore him in the sling, swaddled him, rocked him, did everything I could to provide love and nurturing & bring him (and me) peace. He slept in a rocker at night, and we went through countless "D" batteries; of course the rocker would have to be restarted countless times through the night. I remember singing "silent night" and other songs to him for endless hours through the sleep deprived nights. We took long drives in the car, in case the vibration helped soothe him.
We decided to never have another child. Now that I'm pregnant 6 years later, I think we've forgotten somehow how rough those first few months were. Your post reminds me!
COLIC IS HELL.
But now that I'm on the other side..... colic does end. Our children grow up, and in the big picture, 2 months is nothing. YOU ARE NOT A BAD MOM and YOU ARE NOT RESPONSIBLE FOR THIS. You are going through something that every mother w/ a colicky child experiences. There are discussion boards that focus on this, please find them. They helped me get through the experience.
You will eventually LOVE being a mother and feel competent. You just have to get over this period, and please remember, it will end. All of this will be just a distant memory. Your daughter may eventually have a calm, easy-going temperament & will bring pure joy to your life. The experience of colic has nothing to do with her personality, or your mothering skills. Just take it one day at a time & look forward to the 3-month mark.
In the meantime, if you can find anyone to help you by watching your baby, please ask them! You need to reach out for help. It is essential that you get at least 4 hrs of uninterrupted sleep each day. You need frequent naps. Getting sleep is key to getting through this.