Re:1990 Eclipse wont start!!!!

I hope someone can help me so here goes......Me and my brother were repairing the head and finishing the timing on my 1990 eclipse, we got all done and tried to start it....sounded normal at first and we heard a popping sound from the throttle body area......then a clicking sound starting coming from it.......we took it apart and found that the iac was locked up.......we replaced the throttle body and checked the head for any bent valves.......seemed fine so we put everything back together. It turns over but wont start......thought the battery sounded a little drained so we tried jumping it still nothing. It sounds like a car thats battery is dead it just keeps sounding weaker the more you try to start it, but the battery is only a month old. my brother thinks it might be electrical what do you think?What else could the problem be???? Any ideas would be great.

thanks in advance,
Nick