Intermitten Problem with Acceleration

I have a 1999 Camry with 130,000 miles. About 3 weeks ago my car began to hesitate while I was driving it. It did it twice in one day. A friend suggested that I might have some bad gas. Luckily I had less than a quarter of a tank left so I filled it out at another gas station. The car ran fine for 2 and half weeks until I needed a fill up again. I went to my regular gas station thinking it would be fine to use again. I filled up the tank and that same day the car hesitated again, I will be driving at 40 mph and then all of a sudden it gets sluggish and I can't accelaterate, it lasts for just a few seconds. I put some dry gas in thinking it was the gas. The car ran fine for a day and then the following day it did it again. Does this sound like a problem with the gas or a more major problem?