Get checked by a doctor anyway. Feeling fine right after a wreck doesn't mean you walked away uninjured, and some of the most common crash injuries don't show up for hours or even days.
Here's why. Your body floods with adrenaline after an impact, and that can mask pain and stiffness while you're standing on the shoulder trading insurance info. Whiplash, concussions, soft-tissue damage, and back or neck injuries often set in later, once the adrenaline wears off and the swelling builds. See neck injuries and back injuries for how those tend to develop.
So see a doctor within a day or two, even for a minor fender bender. It protects your health first, and it creates a medical record that ties your injuries to the crash. When you delay, the insurance adjuster will argue you weren't really hurt, or that something else caused it.
A few San Diego specifics. California gives you two years to file most personal injury claims under Code of Civil Procedure section 335.1, but claims against a public entity, like a city bus or a county vehicle, can have much shorter deadlines. Don't wait to find out which rule applies to you. And whatever you do, be careful giving a recorded statement or saying "I'm fine" to the other driver's insurer before you've been examined.
This is general information, not legal advice, and every case turns on its own facts.
If you were in a car accident and aren't sure whether you're hurt, talk it through with someone. Call Crudo Law at (858) 622-7280 or reach out through our contact page. The consultation is free.