You have a right to bring a claim against the Sheriff in his official capacity. Under Florida law, you cannot sue the officer who hit you, because individual government employees are granted immunity from suit under Florida law. There is a 6-month presuit notice requirement. Whether or not you win a lawsuit depends on the evidence presented by both sides and how a jury views that evidence. Suing a Sheriff in his home county is never an easy task, but if you can present sufficient evidence at trial you might very well win.
I agree with the other attorney but wanted to add that the damages against the County Sheriff would be capped at 100K.
What you should focus on at this point is getting proper treatment for your injuries. Not only is this important for health reasons but also will document any injuries that you may have.
Make sure you take photos of your vehicle along with your injuries and keep a record of any expenses that you may incur as a result of these injuries.
Sign up to receive a 3-part series of useful information and advice about personal injury law.