10 pound gain in two days?

Mblaqsidetoside

Hello
I'm writing because my scale is scaring me a little bit. I will admit I am someone obsessed with weighing myself and I'm trying really hard to cut back on that habit, but I weighed myself today after two days and it said I was 10 lbs heavier than I was before. I know there's know way I could have gained that much back but I would like to ask about if what I think is causing it possibly the culprit.
In the past few days I have stayed under my calorie count, one day being by a fair amount. However I've noticed that my sodium intake has been way above the normal and in the red. Along with that, I believe my time of the month may be approaching and I know that I get bloated beforehand. Thirdly, I have been sick with pneumonia for the past month and just finished the medication. I'm curious if that could have an effect.

I'm going to try to control my sodium intake especially these next few days and I only drink water and tea as well. If I do that and take some walks and such, do you think I will be back to normal soon?

Also, is there anything I should be concerned about?