Fair compensation??

Hello I live in CA and last year a man driving an SVU sped out of his driveway and collided with me. Luckily neither of us were badly hurt, so it seemed at the time. The following day I couldn't bend down. I called my lawyer who sent me to a doctor who determined that I had severe visible muscle spasm in my lumber region and recommended about 6 or so months. An MRI was also ordered which confirmed 3 herniated discs. Nothing too major, but major enough that I still get occasional pangs, and was pretty much unable to sit for the first month. The car damages were about $2K. The other motorist was unisured. My uninsured motorist coverage is $30K. My lawyer recently called and stated that they would like to settle for $7,500. What seems unreasonable to me was that she told me that since I am overweight, the medical experts determined that the impact of the crash could not have possibly caused the extent of injuries which I sustained, therefore I must've had some prior damages, and the amount was lowered. I asked her if they are in possession of any prior Xrays or MRIs that they had to juxtapose this and she stated that she did not know as they would not show her the file . Her opinion was to settle and move on, which part of me agrees with, but the low amount of money seems to have a shady basis. Even if we assume that I have had previous injuries, since his negligence is the cause ofworsening a pre-existing condition, aren't I entitled to full compensation? Wasnt that the andquot;eggshellandquot; ruling?? Thanks.