Flag Content?

This summer I installed a prehung door to replace the old service door on my garage. I used low expanding foam around it, and everything seemed to be fine, until it started getting cold. Now the door strikes the jamb at the very bottom, just above the threshold. There is one course of block above the floor of garage, and if the interference doesn't go away in the spring, the only thing I can think of to do is cut out the foam with a reciprocating saw and use some sort of masonry fastener to pull jamb towards the block (and away from the door). Am I on the right track or have done something terribly wrong already? Thanks!