What should I take into consideration when accepting a settlement from an auto accident? I do not have an attorney. I received medical treatment(therapy, etc.).

Make sure you keep a record of everything; buy a folder specifically for all treatment you have had, receipts, etc. The more documentation you have, the better. Make sure your doctor notes in your medical records that your pain/condition is due to a MVA occurring on such and such a date.
The at fault party's insurance company will try to get you to sign off on treatment. DO NOT DO THIS-- even if you feel better, you do not know what long term effects it may have on you or if years later, the pain or condition will return. Signing off on this will dis-entitle you to any benefits at a later date, even a follow up consult.
If you did not file a police report, make sure you do this IMMEDIATELY. Do not admit any fault or wrong doing when you do this or make a statement. Doing so may cause limitations or restrictions to any potential subrogation.
Play hardball with the insurer. Insurance is supposed to put you back to the place you were at before the incident. You deserve the right to the care you need, where you want to have it and when you want to have it.
This is all I can think of off hand right now, but I will certainly update you if I think of anything else. Best of luck to you!

What should I take into consideration when accepting a settlement from an auto accident? I do not have an attorney. I received medical treatment(therapy, etc.).

No matter where you are, or what kind of injuries you have... ALWAYS get a lawyer. The amount you pay in fees is nothing compared to the increase in your settlement. Insurance companies treat people without attornies like the suckers they are, and pay them accordingly.

First is the injury minor, or will or could it possibly cause future problems ? If you have to go to the doctor 30 times over the next 10 years those costs are hard to figure.

Loss of work, travel to and from the doctor

Repair of your auto, but also value, a wrecked auto even fixed as good as new has a lower re-sale value. A 20 K auto could be worth 2 or 3 K less because of the accident.

And normally the insurance company will try to settle much lower than they will finally settle.