Dear nic: Gosh, there is no way to know if they will be permanent until a true diagnosis is made. Typically pinch marks are small broken blood vessels--these tend to resolve in time. The red marks may actually be coincidental to the pinching. If this is the case, and they are actually a dermatology condition, they might resolve after treatment. Lastly, if it is a structural thing (eg cherry angioma), like moles these will tend remain as they are. Seeing your OB is the best idea so they can give you a conclusive diagnosis.
Yours,
Jane