should I see my doctor?

Okay so, I am not sure if I should see my docotor or wait it out?! My April period (first week of the month) was lighter than normal and of course I was bloated, but the bloating never went away, along with the nausea, and being tired. But the bloating is the worst, so bad that at times it's hard to breath.   I was 5 days late on this months period(may) and it was spotting and extremely lighter than normal. I tested 3 times before I started and all of the results said negative. But in the past week alone I've gained 5 pounds and that's not normal for me, I have a problem gaining weight, I was 82 pounds for a year with trying to gain and this morning I weighted in at 87.