I think I had a miscarriage and had HEAVY bleeding and grey and pink clots with pink mucus and I havent had a period in 3mo and my doctor said she cant prove I was pregnant or not?

I'm sorry to hear that you're going through this difficult situation. Heavy bleeding and passing clots can be signs of a miscarriage, but it's important to consult with your doctor for a thorough evaluation. If you haven't had a period in three months, it may also be worth discussing other potential causes with your healthcare provider. Keeping track of your symptoms and any changes can help in your next appointment.