My insurance company sent me a letter saying my claim has been closed. Does this mean I can't go after additional money for damages?

No, that is a standard practice by insurance carriers to make you feel like the claim has been closed. You can have the claim reopened as long as you did not sign a “release” for the settlement offer provided. If you feel you were underpaid on your claim then you should call a Experienced Public Adjuster for a Free Claim Evaluation. (407) 212-8669