Need your comments...

I was hit by a car (Rear-end) not my fault, 6 months ago. I had a
concussion and had to undergo all Physical therapy, Chiro etc...Not
recovered completely, but tired of doing all this. I sold my beautiful
BMW...:(. Long storu short, the other party insurance took care of all
my current bills. I am still suffering from pain, thinking of signing
off. What should I consider? & how much should i ask for compensation?
(if i were to sign off).