Battery trouble

Last November my car battery died on me and I bought a new one and now my car won't start again. Could it be that the battery, which I have only had for 6 months, is dead or is it something more serious? I opened the hood and noticed that the cords are still connected to the positive and negative terminals but some how the battery itself has come loses from the screws holding it down and that I'm able to pick it up while still connected. Could this be the problem? I got a boost yesterday and it started jut fine and I drove it around for a few monutes to warm it up but now it won't start again. Any help would be greatly appreciated.

Battery light on?
Most auto parts stores will test your battery and alternator.

The hold down bolts should have no affect, unless it was jossled around and cracked the case, which is not the case here....

You said it started with a jump.....as Aleekat asked, was the battery light on while it ran? Do you have a gauge in the dash? Does it show that it is charging?

If the battery died due to a draw, the source of the draw has to be found(parasitic test needs to be done)......make sure the battery cable connections are clean and tight.....

Since it seems that your battery was very discharged(I assume it wouldn't even crank?), jump starting the car and letting it run for a little while is NOT going to recharge your battery....YOU DO NOT CHARGE DEAD BATTERIES WITH ALTERNATORS.......You can damage alternators this way......they are not built to be chargers......they are there just to help to recharge the battery due to discharge caused by cranking the engine, when too many accessories are on, and normal discharge caused by cars sitting for long periods of time.....

Au contraire... A loose battery bouncing and sliding around will become short lived. Especially under severe conditions. At the very least your cables and clamps can become loose. Battery post and plate straps can break. Terminal pads or post sealing to the case gets damaged and you begin to get that "bleu cheese" dressing on them and the cables become saturated with corrosion within a coupla inches of the battery. They don't put battery hold down brackets in 'em for nothing.

I agree....if you are off roading with your vehicle, that could be a problem....but normal driving I don't think so......I'd be leaning more towards a draw....