Still burping the next day

So I tried fish oil yesterday for the first time. I decided to take 6x 1g tablets before a meal when only 4 was recommended. They are 180EPA/120DHA tablets. It felt like they never digested properly, I can feel something in my stomach ever since taking them. Its been 24hrs and I am still burping and can still feel odd in my stomach. the feeling is worse when i haven't eaten for a while.

The amount I took doesn't seem like a lot, I've heard of people taking a lot more than me.

Whats going on? What would the feeling in my abdomen be? I thought it could be the capsules, they seems so solid.

Any ideas? Also have had more bowel movements that normal, but pain/feeling remains unchanged. Tweet