Crankshaft position sensor failing ?

Ok so my car has recently been ACTING really horrible lately usually when I come back to starting it after coming from somewhere , & will just Crank & not turn over I tried everything but find out if I let it sit for a while & come back it will start up finnaly & sometimes while I'm driving it will start to idle rough & almost seem to stall or die out , I'm getting check engine light & was curious if I should replace both sensor's , crank & cam sensor's since they work together.. anyone have an idea ? 130, miles also think I might need to change spark plugs after replacing the head gasket for leaks.