KJ is 5 months

I can't believe my little baby is already five months. She still feels like my little newborn that I brought home from the hospital. Maybe it's because all she ever does is cry, eat, and poop. Still hasn't grown out of that newborn phase yet, I suppose. I say forget water boarding, let's use a screaming infant to torture people. It's enough to literally feel like you are losing your mind.
Shortly before Karsyn turned 3 modnths, she started getting really fussy all the time. I thought she was starting to teeth, and also remembered from Raegan (who was the best baby) that month 3 was just tough. So I was patient and waited for it to end. Only it hasn't. Since she was in the NICU for a week, she had a nurse who would do monthly home visits with her. With her fussiness and the amount of ones she spit up while the nurse was there, the nurse suggested we talk to our pediatrician about reflux. So I did. Dr said it did look like it, so she was put on a Zantac prescription. We left for California and she was a dream baby. Absolutely perfect in the car, which before we had never been able to be in the car for more than five minutes before she would start screaming until she would choke. I figured the medicine was working and all was well. But then the crying came back and got worse. She cries all day, and wakes up throughout the night. I have tried swaddling, teething gel, teething tablets, teething knecklace, Tylenol, gripe water, gas drops, switching formula. I have tried it all and she still doesn't stop crying. I took her into a pediatrician up here that suggested maybe she is having a reverse reaction on the Zantac and it's making her feel worse. So we took her off it. He also suggested we get an upper GI x-ray to rule out any issues with her digestive tract. We have one scheduled in August as soon as Tyler gets back. And so I hold on to every ounce of patience I have in me, and hold my screaming baby day and night. We hope to either have an answer soon, or she will just outgrow whatever this is. We love this little girl, and just want to see her happy. Mom could really use a night of sleep too!!!!