If the crash occured in August and you have already had the independent medical examination, then you have suffered the typical claims management firm syndrome of being rushed through the system so that they get paid and you end up with a claim being severely undervalued.
Unfortunately, most people only realise how bad these claim management firms are once they are brainwashed into using them, and has been seen on this forum on many occasions, they have no expertise what so ever and 99% of them are a complete waste of space. Legal Insurance provided law firms are only interested in putting you onto their conveyor belt and normally have paralegals or legal execs handling LEI claims, and so they in many cases are just as bad as the claims management firms.
Yoour medical examination should not have been carried out until probably 9 - 12 months after the injuries were sustained as by that time you would have either recovered fully, or if there are ongoing problems are more accurate prognosis can be made which affects the value of your claim.
You can easily change your legal representation without incuuring costs.
Find a law firm who specialises in personal injury of your choosing. They will apply for your file from the previous law firm and then provide an undertaking to pay the old law firms reasonable costs at the completion and settlement of your claim. you will not be required to pay anything.
Your case can continue to be funded under legal expenses, or if your insurers decline (which they have more difficulty in doing these days) then your case can still be funded under a conditional fee agreement (no win no fee) which still guarantees that you keep 100% of your compensation, and your new law firm will claim their costs from the other side.