Rear-ended in California

I was recently rear-ended in California. I was driving toward an exit and had to stop because of another vehicle in front of me. The car behind me rear-ended my vehicle, and the other driver was determined to be 100% at fault.

I initially filed the property damage claim with the at-fault driver's insurance. They gave me an initial repair estimate, but after the actual repair estimate came back higher, they told me the damages exceeded their insured's property damage coverage/limit and they would not handle the full repair.

Because of that, I filed the repair claim through my own insurance. My insurance is covering the repair and will pursue subrogation against the at-fault driver's insurance.

Separately, I've been dealing with the bodily injury claim directly with the at-fault driver's insurance. I went to the ER after the accident and have had multiple follow-up doctor visits/treatment.

They initially offered me $2,300 for pain and suffering. I asked them to increase it, and they came back with $3,300, saying they wouldn't go higher.

I have a few questions for anyone familiar with California auto claims:

1. Pain and suffering: Does $3,300 sound reasonable considering an ER visit and multiple follow-up doctor visits? Should I continue negotiating, and if so, what kind of documentation/evidence would help justify a higher amount?
2. Diminished value: Since my own insurance is paying for the vehicle repairs and pursuing subrogation, who should I submit a diminished-value claim to?
3. Anything else I should be doing? Are there other types of compensation, reimbursement, documentation, or claims I should be considering before settling the bodily injury/property damage portions of the claim?

I'm mainly trying to make sure I don't sign a settlement or release before understanding what claims I may still have.

Would appreciate advice from anyone who has dealt with a similar California accident/insurance situation.