Sean Gorham

I have a 2005 blazer 4x4. First let me say that ive searched the net with no avail. I recently changed my brake calipers etc. After i bled the brakes, the next day saw that my helper left key on all night so the battery died. Got a new one put it in and now blazer wont start. It does nothing. No clicking no lights nothing. Everything worked before battery died. Its not the starter or battery terminals or fuses or any of thing basic. Any ideas of what is wrong or how i can fix it.