marks due to sensitive skin rubbing against hard and tight clothes or it can be start of stretch marks. When stretch marks appear then they are initially red and then turn to glistening white. Stretch marks can appear when there is rapid
I suggest you to get it evaluated from a dermatologist.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.