i just recently took my car into the shop to replace the timing belt. i bought a gates racing timing belt for them to change out. they changed it out and i drove it home. a week later i noticed a leak in my oil line. drove it back to the shop to get that fix, drove it home. a week later i took off the timing belt cover. i noticed there were already threads coming from the side of the belt. and looks like it is rubbing against something that cause to have black marks on the blue outline of the belt. is it normal for that? or should i get it checked out. car was not even driven over 20 miles since the timing belt install.