Weight gain without changes in diet/routines. Constipation?

25F 5’3” and currently 139lbs.

I’ve noticed over the last several months my weight has been increasing but I have not changed anything in my diet or routines. A few months ago I was averaging 134-135lbs but it seems like I just keep gaining weight even when I necessarily didn’t even eat during the day.

I do struggle with chronic constipation so I’m wondering if all the weight gain is just bad gut biome?? I feel bloated/look like I could be 4 months pregnant all day everyday it never goes away.

Does anyone else experience this? Im concerned it could be medical related :/