A couple of days ago , I left my lights on in the truck, when I went to leave for work, the truck was dead. My neighbor gave me a jump. Now when I start the truck, it kind of seem weak, and the lights in the inside are very dim, after a few seconds, they brighten up again. Bad battery or something else..

 

Now how would we know what state of condition your battery is in??????????????????
How old is it, how many miles on your truck?
Have you taken it in to have it recharged and tested, since jumping it and driving around the block won't charge it?
Get is checked at a local parts store, voltage should be between 13.6 and 14.4 with the engine running, what is yours?

 

If the Battery is more than three years old ,replace it.

 

don't check voltage on a battery with the engine running, check it while it is off so you will know, comes back with something like 6 volts like mine just did you know you have a bad battery for sure, when the engine is running the alternator will be charging and it will always read 12-14 volts