Is it my crank sensor?

Ok my car has been messing up for awhile its 95 oldsmobile cutlass supreme. It started of just one time starting hard and gradually has gotten worse. Sometimes usually after sitting for a few hours it will start fine and run fine. I will get to the store and park and turn it off, get done come out it will crank and crank and if it turns over i will give it gas and it acts like its not getting any and it will chug an eventually stall out, even if i get it running i have to drive it around the parking lot to ensure it doesnt stall out in the road. It is now to the point where it cranks and cranks and wont turn over, just changed the fuel filter.