Open Question: Insurance Settlement What to expect?

Well I want to try and get answers to make sure that im not getting screwed over. this is the first accident I have been in and it wasnt my fault. I was home on leave (Active Duty Army) and was rear ended by a ford minivan. I was stopped turning left when he hit my car. I was driving a 2007 Ford Taurus. Well I wasnt the driver but I was in the back seat and took the brunt of the impact. Now I am a Soldier and I dont tend to show weakness but I got injured. It tweaked my back and shoulder pretty good. well I went to the ER and got xrays and some medications that day. When I got back to my unit I went to the Aid station, they took a set of xrays as well. It was determined I had a strain in the rhomboid muscles left side and a lower lumbar sprain. I was placed on a physical profile limiting my capabilities to perform my job as a Sergeant for 2 months. I also went to physical therapy. I was unable to attend my promotion board to E-6 Staff Sergeant that following month due to my physical limitations. the damage to the car was only about 600 dollars, so im afraid that they are going to try and down play my injuries and settlement based on the damage to the car. I am trying to avoid getting an attorney, but would like to know a rough estimate of what most people and insurance adjusters would think fair.