i have pain in my stomach too since monday so it's 3 days now. I knew it's not normal pain so i called the doctor. I think if you are not sure what it is, maybe it's worth calling the doctor and explain what the pain is like, at least it will relieve you worries.
In my case, there's not mush to worry but i was told to rest more and stray at home. It might be different in your case though. Hope everything goes well