Abdominal Pain: Multiple questions regarding recent ER visit

I (46M) went to the ER 4 days ago with severe abdominal pain that had been ongoing and increasing for 3 days. The pain was just under the sternum and radiated to the entire abdominal area as well as my back, but not quite kidney territory. I had taken OTC laxative, pepto bismol and an alka seltzer, thinking maybe it was constipation/gas. Nothing helped or eased the pain. Pain level peaked to a 7-8 out of 10. Got a ride to the hospital.

Was in the ER waiting room for ~7 hours where I experienced continued discomfort and at one point intense sharp pain (level 9ish) that lasted about 20-30 minutes. Finally was seen: was sent for bloodwork, Ultrasound, and CT. Scans came back with “not much” (PA’s words) to point to my pain. I was THEN (10-12 hours after arriving) offered pain meds (intravenous Tylenol)and was diagnosed with pancreatitis based on blood work. The PA told me I must be an alcoholic because that’s who gets pancreatitis. (I’m far from an alcoholic, but now am incredibly angry and insulted). Never saw a doctor. Not saying anything bad about Nurses or Physician’s Assistants, but if I was this much of a puzzlement, maybe a doctor could have tapped in as well… (I hope I do not sound insulting now)

The reason I’m inquiring with Reddit Doctors is that I feel I have been misdiagnosed. I feel as though I may have passed a gall stone, which may have irritated the pancreas and caused me such “discomfort”. How likely is it that such a thing could have been missed if it had passed while I decayed in the waiting room? And would a second opinion be worthwhile now that I am thankfully in far less pain, albeit a little sore? (Pain level 1-2)

Follow-up question, the PA told me that Ultrasound saw a mass on my liver, which may be “fatty”. I don’t really understand what that means, and my inquiry to that went ignored. I have made an appt with my PCP, but of course I can’t get in there for another 5 weeks. How concerning should this news be? Discharge paperwork describe it as “a 3.7x3.0x4.1 echogenic mass seen in the liver adjacent to the gallbladder and may be some focal fatty infiltration”

Sorry for so many questions, I am very upset with my treatment and with this news. I appreciate any insight.