You didn't mention much on diet at all. What do you strictly avoid?
If you wanted to go the cheapest route, my first advice would be to go on a STRICT gluten-free, nightshade-free, Paleo diet (no peas or green beans either) for a month and see how your symptoms fare. Also, you must get 9+ hours of sleep a night. I had a patient with suspected UC "fix" the problem simply by doing the above diet, getting more sleep, and taking my heavy-duty probiotics.
If you need to see proof in the form of tests, here we go:
First thing I'd say to do is the "Stool Test for Gluten Sensitivity" at www.enterolab.com
Next, an Intestinal Permeability test through my office (a urine test).
If you were ever concerned or had hunches about parasites playing a role, get the stool test done through www.parasitetesting.com
and list me as your physician (they won't do the test unless they have a doctor to send the results to, but you can order it). You can get my address and other info from my website for the forms.
Then, if nothing showed up yet, we'd talk about food allergy testing. Again, that won't be necessary if you really do the diet above. Make sure you are gluten-free, and I'd highly suggest the book from www.noarthritis.com
on how to exactly avoid the nightshades (they are hidden in as many places as gluten).
Yes, it sounds like it will be tough. It is tough. So is UC.
Also, 10g total of EPA+DHA sounds like a bit much to me, but that's another story.