Battery Drained, recharged, won't start?

[dcardenas]

So in my newbie ignorance, I left the headlights of the X5 on and managed to drain the battery while I was at work one day. I recharged it and it was working well enough, although it seemed to sound a bit weak when turning over and starting.

The past two days, I took the motorcycle because it was just too nice out not to. I went to start it this morning and got some clicks, but no turning over. Used the GF's car for a jump and made it to work fine. Then I go to grab some lunch and again, no turning over.

It seems to me that the battery doesn't have enough juice to get her started. How should I proceed in getting this thing working right? Could a low water level cause this?

Thanks!