1995 Ford Probe iM sick of pushing my car.

Just bought this probe, so excited, first car. Well when I go up hills if I dont get a headstart I end up going about 5mph up the hill, and last night I tried putting it into 2nd or 1st gear (automatic) and it rolled backward even thoough my foot was almost to the floor. I ended up making my girlfriend gas it while I pushed it up the hill, mind you this is not what I would consider a steep hill at all. Also and maybe an unrelated problem when it shifts it jerks the car. All I can think is transmission and if its that then I find a cliff and watch my $900 car explode cuz I cant afford a transmission. Im taking it to a mechanic tomorrow to figure it out, and so they can rape my wallet, but it would be nice if I could at least have an idea. Thanks in advance