whenever I get a couple flats that quick, I get new tubes. though this has only happened to me once my tires are 2500+ miles. I figure the flats are a sign my tires are shot.
I would guess you've got some debris - small metal or glass - imbedded somewhere in your tire that's giving you fits if you're getting so many.
another suggestion: get new rim tape. had a 2 flats on one ride one time, but only one C02 cartridge with me, so as I'm standing there pondering my next step after the 2nd flat, a small group of bikers approaches and stopped. one of the riders just so happened to be the owner of a large LBS. he grabbed my bike and fixed my flat, he had a small pump, and told me to get new rim tape. I did ( at his store, of course ) and it helped.