Achy gut and left rib ache

[BigBing]

Hi. I am a 37 yr old male, fit, health eating. No smoking, etc.  6 months ago I had an achy upper abdomen and slight dull ache at bottom left rib cage. PCP though parasite and trapped gas / splenic flexure, and went on strong probiotic. Said don’t expect difference for a few weeks.  After 3 weeks all went away and was perfect for 3 months.

Then came a bout of really substantial gas a month ago and the rib sensation returned. This has lingered off and on with no specific trigger and more of hollow ache now.  Not what I would call pain, but it’s there.  Visited Gastro. Did blood work, going for ultrasound and endoscopy, and if all good, colonoscopy. He believes IBS with constipation but wants to be thorough. Blood work came back good but I never fasted so not sure if that tweaked any numbers of course? Or how much it can tweak these results?

I have always had an issue with slow moving bowels and take fiber on the regular.  At 19 I had an endoscopy as I was experiencing nausea, indigestion. Diagnosed with a small hiatal hernia and they found crystals in my gall bladder. I am also a chronic worrier!

My questions are:
1. My Lipase number (non fasting) was 244. It shows 23-300 as normal. I see so many different normals out there that I start to doubt the normal... can this raise easily when not fasting?
2. Can trapped gas linger or irritate the colon?
3. Anyone seen this with stomach issues, gastritis, etc?  

It’s mentally holding me down but appetite is strong.  It’s in my head now and that seems to be the battle.  Thanks!