It could be some sort of pigmentation loss, or if you had chicken pox or measles when you were younger, it could be caused from that.
If it's not bothering you, you could wait to see a doctor. If you develop any other symptoms you should see a doctor.
Apart from vitiligo, it can be idiopathic guttate hypomelanosis. It is 2 to 5-mm flat white spots found on the shins and forearms. It can be due to sun damage or ageing. Treatment options include protection from the sun, cryotherapy, dermabrasion or microdermabrasion, tretinoin cream or pinch grafts of normal pigmented skin. I suggest you to get an evaluation done from a dermatologist to confirm the diagnosis.
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.
Thank you so much! I will make an appointment ASAP and let you know how it goes