我在高速公路上被半挂车撞了，但我爸却劝我别请律师。

If the situation is handled by insurance companies the money may go to the policy holder which sounds like your father. If you sue directly, you probably are entitled to the money in a way your father is not. I’m NAL, but I’d definitely get one ASAP. Don’t listen to your father on this, you’re an adult and can seek representation independently.

Sounds like your dad is hiding something about your insurance coverage.

Lawyer up. It may or may not work to your benefit but you really won't know until you meet with the attorney. The attorney will likely take 30-40% of any award and it will take several months. The insurance companies only look out for themselves and it's never to your benefit. Good luck

If something is fishy with your car insurance, I don’t think it’ll matter.

You were in an accident caused by a party that most likely has insurance through the employer or as required if they’re self-employed. If your insurance isn’t going to cover your medical bills, a lawyer will assist you in getting that from the other party, and possibly even more.

I’m not saying what happened to you was great, but the fact that it was caused by semi in most cases, means you are most likely going to receive the monetary assistance you need to make sure you are ok with the help of a lawyer. ( assuming you know who it was of course and they didn’t run off.)

Commercial insurers are really horrible when they deal with claims. If you had more than liability, you'd have an insurance company who could go to bad for you. Without that, I'd at least talk to the lawyer.

Know, though, that the lawyer will probably take 30-40% of whatever your recovery is. With a commercial insurance carrier, the remaining 60-70% may still be more than what they would have given you without representation. But, it might not be.

A concussion might not be that severe of an injury in light of the things that could have happened. Do your doctors think you will have permanent issues? If so, a lawyer will help you go after the insurance company for compensation. If this is "you'll be fine in a few weeks" territory, the insurance company is paying your actual medical bills and they're giving you reasonable value for the car you lost, then getting somebody to take 30-40% off the top probably doesn't make sense.