What did I do?!!!!!!

I blew a head gasket on my 94 Beretta 3.1. So I picked up a Chilton manual and followed the it the letter. Now it doesn't start unless I pump the throttle rapidly and when it starts, it runs like the timing is off, backfiring and really rough. It will not idle on its own at all and white smoke out the exhaust. I think I botched the job. Help please!

OK. So No one has an idea. I should have taken the heads in to get done. Turns out I have 2 bad exhaust valves.

Changing the head gasket was done due to a compression issue I presume. There are more related issues than just the gasket. Everytime I pull a head, I flip it over and make sure all the valves are closed and do the "Water test". I simply pour water into the cumbustion part of the head and if it can't hold water, it can't compress air.