Vomiting after giving birth

Hi all,

I have given birth February 2022 so my baby is going to be 4 month’s now.

I have been having this new symptoms which is vomiting before and after periods. Now my periods ended and still i am having this symptom is it normal?

I asked my gynae and he says that vomiting has nothing to do with period, previously I do have nausea but didn’t vomit during period.

I have check on then pregnancy test, twice both came up Negative.

If it is stomach flu, my whole system would be down right? But I can go ahead with my day, not sure if I est late or eat too much?