I recently had a flat on the right front tire, had it repaired, and everything seemed fine. But ever since, there has been this light grinding/ pulsating squeaking noise from the right front somewhere. It doesn't sound like anything is lodged in there, and I can't see what would be causing the noise. I also checked the guard over the rotor to make sure it didn't get bent and rub anything. Please Help! This is driving me nuts!

Did you just do a cursory exam of the brakes or really check them for rubbing. Its possible that the caliper wasn't bent, just misaligned. Have you checked the torque on the lug nuts?