Call me stupid or w/e but I misshifted from 3rd gear redline back down to 2nd. After that everything seems ok but there is a ticking/slapping sound at idle which increases with the rpm and my temperature gauge is stops a tad shorter than it usually does.

Another question:
What are the symtoms of a bent or multiple bent valves?

 

you definitely could have done a mechanical over-rev and bent some valves ... especially if you say there's ticking. only way to know for sure is to pull the valve cover (and maybe a whole lot more) to find out. bring the car in for compression and leakdown tests.