All that warmongering probably left your science in shambles. What are the victory conditions? I would recommend doing everthing you can to get the major techs (like trading with a friend), and just focusing on getting back up to speed unless it's a conquest victory, work for the military techs and just wipe everyone else out.
Edit: You can also hover your mouse over the score screen in the lower right hand corner, on your name it will give you a breakdown of your points, so you can kind of see what area you are lacking in (science, land area, etc.)