You're lucky to have walked away from this potentially serious event. People can sustain significant injuries to their head, neck, lower back, joints & bones. At the very least, there should be an evaluation by a physician (primary care of orthopedic surgeon) with x-rays of any areas that are painful.
If you are concerned about not having insurance
, don't put your well-being at risk. Emergency rooms are required to provide all of the services that you need. But if you don't have insurance and are concerned about getting stuck with a big bill, the government has set up clinics call fqhcs (federally qualified health clinics) that will provide you services at little or no charge, depending on your need.
Depending on where you live, there are likely several of these fqhc locations within 15-30 minutes of your residence. Do yourself a favor and don't ignore pain, it could be telling you something important.