The Parking Brake light is coming on when I brake firmly on my 2007...

[jazzpiano420]

...Chrysler Sebring Touring.? I was driving down the road in my new car (bought 2 months ago) when I stopped hard for a yellow light. Immediately after I came to a complete stop, the parking brake light came on. I checked that brake and it was not engaged, and started blinking when I tried engaging then unengaging it.
Since then it has happened frequently (4-12x a day) It occurs seemingly at random, I can be braking hard, firmly, or lightly, and it randomly will turn on when I come to a stop. I have not felt a "pull" to one side, and the light goes off after 10-15 seconds after I take my foot off the brake. Even though I don't feel a "Pull", I'm thinking it might just be a partially stuck piston on my calipers. Anyone else wish to share their thoughts?

P.S. Please don't comment on how I shouldn't have got this car or that I should sell/scrap/trade it in. I'm stuck with the vehicle so I'm trying to make the best of it.