I had my gallbladder removed in late August. I too had the "bellybutton" surgery.
It can take six weeks (or more) for what some people call "phantom" gallbladder pain to resolve.
When food leaves your stomach, it does so in the form of a paste called "chyme". Your duodenum (the first part of your small intestine) senses fat and tells your liver and gallbladder, "Send me some bile."
Your duodenum is still sending cholecystokinin (the hormone that says, I need bile) to what it thinks is your gallbladder. Cholecystokinin is a hormone that causes spasms. Your body (and mine too) is confused, and adjacent structures (including those ducts) may be having spasms anyway.
Your liver is still sending bile, but it may not "know" how much bile to send.
I have not resumed a normal diet yet. Sometimes after cholecystectomy (gallbladder surgery), people need to eat a low-fat diet for a long time. I am still on a very-restricted-fat diet, but then I also had pancreatitis at the same time.
You may have to be patient. If the "certain foods" are high-fat foods, you may not be able to eat them like you did before. Re-introduce fats into your diet very slowly. If a food bothers you, you may have to avoid it in the future.
I sleep on my left side. I've noticed discomfort when I sleep on the right side.
All this does not sound like much fun, but some people don't have to change a thing after gallbladder surgery, and some have to make major dietary changes.
There are a lot of resources for "pain after cholecystectomy" and you may want to do a search to see if any of the information pertains to you.
Although a cholecystectomy is the most common surgery in the United States, and although the gallbladder is a hollow organ, it's still an organ that your body was using for many years, and now it's gone. Your body may take some time to recover.
Healthcare teaching assistant.