Women can gain anywhere from 1/2 pound to TEN pounds during their cycle, it's mostly water. Frustrating, but don't give up! Know that things will be back to normal pretty quickly. Over time you may notice that there are things that make your cycle better or worse. Pay attention and you may be able to make yourself feel better during these rough times. But know that you are not alone, most of us go through that (I'm 55, have no more periods, yet I still have some of the same symptoms and know when my cycle would be happening, if I still had them).
You can always check with your doctor to make sure your levels are good (iron, vitamins, etc). Just for piece of mind.
Good luck, and don't quit! You are doing something for yourself that will make things better in the long run. That "long run" comes around a lot faster than you think!