Yes, you absolutely must seek medical care. Even if you feel fine, you could be suffering from unseen or hidden wounds, including internal lacerations, concussion, or soft-tissue damage, which can be masked by an increase in adrenaline directly following the crash. Some of these injuries, seemingly minor at first, can become major or even life-threatening problems if not treated properly. Also, if you refuse medical attention or fail to follow up with a doctor, you may forfeit compensation later on.