Is it okay to scratch my scalp with a brush in the shower to get rid of hair concealer fibers that get stuck to my skin?

Thank you for your question. Our patients are advised to wait 2 weeks after the surgery to begin to gently treat their scalp. You are probably okay to do so at the 2 month mark, however, I suggest that you discuss with your board certified facial plastic surgeon, and follow their recovery guidelines.
Best wishes,

Scratching your scalp everyday, 2 months post-op, may damage your scalp, but it should not damage your grafts if you can stop it now. Whatever chemical you are using to adhere the fibers to the scalp is too strong. You need to change to a better, less adhesive product. Consult your surgeon for assistance.

At 2-month period, it would be alright as long as it doesn't cause bleeding, redness, soreness or pain. 

At two months, you are no more likely to damage your grafts than you are to damage native hair follicle with a scrub brush.  That said, depending on how stiff and sharp the bristles are, and how hard you scrub, it would be possible for you to cause damage to your skin.  You may want to consider checking with your surgeon, even showing the brush and your scrubbing technique.

Never brush heavily.  USe a good shampoo and leave it on for 15 minutes using your finger tips over and over again to remove it