If you're sure that she's got the egg spot and that she's a female, then don't worry about it too much.
I've noticed this behaviour whenever I pick up a female from the LFS, there is always a couple of dominant females in every tank and they will nip the others and they will flare at each other.
To help the other females I guess you could introduce more hiding spaces in the tank, eg rocks, driftwood, pvc piping, plastic caves, plants, etc.
From what I've noticed, the females being chased still appear to be healthy and fine, except maybe the occasional fin tear, so I think it's all just part of nature.
PS I realised that I didn't address your first question haha.. Bloating could be a a sign of swim bladder infection, or she could just be really filled with eggs. To err on the safe side, better to quarantine her for observation. I'm not sure if there are medications for swim bladder infection, but maybe your LFS could help you out with that..