1993 Buick Park Avenue antifreeze

Replaced radiator coz little radiator inside was bad and had transmmission fluid with antifreeze. My mechanic/friend said I needed to get it powerflushed after he replaced the radiator for me. Coz he did what he could. But I wasn't able to coz of no money. It was done on the 9 th of jan 2010. I've driven about 700 miles since and this morning it wouldn't shift, it's a quart & half low and anti-freeze is leaking by the transmission. I can't get hold of my friend and worried sick. Is it going to be a big problem? He said it might be ok to wait a few days but it's been 2 weeks. I maybe average 40 miles a day driving. I'd like your opion/advice.