I recently had mohs surgery on my forehead. When can I expect the bruises to fade?

Post op bruising can last 1-2 weeks. I would recommend you discuss and be examined by a board certified dermatologist before rendering any opinion on this question.

It can take several weeks for bruises to fade if you take coumadin and get a bruise. They will go away, but it does take time. A normal bruise when you aren't on meds like this can take up to 2 weeks, so when you do happen to take meds like coumadin, it can be 4 weeks or more. "This answer has been solicited without seeing this patient and
cannot be held as true medical advice, but only opinion. Seek in-person
treatment with a trained medical professional for appropriate care."