My 1995 Firebird was starting to run low on gas, so I put about 2-3 gallons in it. I drove to school. About 4-5 miles into the drive, my car started coughing whenever I had to go slow, especially when trying to take off. Temporarily fixing the problem, I would put it down into 1st, then 2nd, 3rd, and then just up into D. That afternoon, I went to go start it, and it acted like it wasn't getting any gas. Any ideas?

fuel pump or fuel filter, you let it run almost out of gas?