Hey everyone, I just got my car off the jack after painting a caliper and now it doesn't start. There werent any lights on, key was out of the ignition the whole time. The battery has is running at 9.3v and the starter clicks but the engine won't roll over. I've tried jump starting it and the same thing happens. I just bought this car monday and I'm very ticked off about this right now. Any help would be greatly appreciated.

P.s. I read somewhere to connect the negative battery cable to the positive for a minute and that didn't help...