pushed in on crap, tell me odds

[jaydoggie]

blinds 100/200 my total stack 750. and in SB

folds to c/o who doubles to 400.
button folds, after posting my 100 i have 650.
J[img]/images/graemlins/heart.gif[/img]4[img]/images/graemlins/heart.gif[/img]
BB is average stack, pretty certain hes going to fold.

i dont fully understand the pot odds in this situation but i know im behind.

total pot at this point 700. my stack 650. should i have pushed or waited?