check you oil. if you were running low you might have damaged a main or rod bearing. internal engine damage makes wierd noises-- ticking thumping knocking grinding--. check compression, may have burnt a valve or fried a ring... how many miles on the car? high mileage engines build up carbon on rings and carbon actually seals the piston. high reving can blow the carbon out of the rings and ruin the compression in that cyl.