Karen,
I left work 1/24/11. In April, 2011 I filled for SSDI, Everyone says you will get denied several times, so in June or July I signed the paper work with a SSDI atty.
August 23, 2011, I was approved, so I didn't need the atty. I would wait till you get denied before getting a lawyer involved.

Paper work seems to go on for several weeks.