93 hesitating

It all started after I put gas in my tank on christmas. I put in the middle grade; but at a place I don't usually goto. Only went because down the street from the house and my cousin was stuck and need a ride.

Now when it starts it stubmles or acts like it wants to die. The rpm needle only jumps around nothing over 1000rpm usually 100rpm to 300rpm. When I start to drive it does it to but no as bad. Then I stop at a light and it wants to die. It has been like this for about 2 days now. I added iso heet & injector cleaner and still nothing. So I was thinking it is my fuel pump but not sure. Don't want to by one and not the problem.


Also their is a clicking noise from under the hood. But I think it is the alternator. How do I check to see if it is still good? Remove the negative or positive from the battery post?


Thanks