Bodily injury settlement too low?

After much research I sent a demand letter to my insurance company for an uninsured motorist bodily injury claim. I requested pain and suffering, medical bills, future medical bills and reimbursement for child care, cleaning, mileage, etc. I sent copies of all my medical bill, receipts and a letter from my orthopedic surgeon doenting the permanency of my injury (broken heel). I asked for 10K under my coverage limit and I got a call to pick up the check within two weeks. My question is this : in his letter to me he stated: "Accepting the enclosed payment will not prevent you from requesting payment of additional damages under your policy. If you feel you are entitled to payment of additional damages please contact me immediately." Does this mean my claim is worth more than I thought? I was expecting to be low balled, so I did not follow my instincts to ask for my coverage limits. Also, does this mean he thought my settlement was too low or is this standard practice if coverage limits have not been met? I'm just asking for fair compensation as I still have a long road to recovery ahead of me.