Tommy,
I have great days and bad days too. It usually has to do with the quality of sleep I am getting. Also stress loads can ruin my day. By stress loads I mean things that cause mental stresses. It may be reading the newspaper etc, listening to the wrong kind of music, taking on a difficult task, or anything that requires concentration to complete. Sometimes, it is just a stimulus that takes brain power to tolerate, such as sounds, etc. Think of your brain like a pulled hamstring. It can do light work but it is not ready for heavy lifting.

I am confused about this PTSD issue? What even would cause your PTSD? It sounds more like you have depression. It is not uncommon to get depression after a head injury.

How is your diet? Do you take any vitamin supplements? B vitamins are VERY important to brain health. If I go without my vitamins, by the second day, I am a mess.

I need about 100 mg of B-6, 500mcg of B-12, a broad spectrum of all of the other vitamins and minerals, fish oil, niacin, etc. I take 21 pills every morning, including five that are meds.

Who is treating you? It sounds like just a family doctor. You should find a physiatrist who is knowledgeable in head injuries. They usually are listed under "physical medicine and rehabilitation."
How old are you? That can make a serious difference in recover times and other symptoms. The brain is doing a lot of internal work just growing and maturing until you hit 25 years old. It is high school years that are the most critical.

I have more to say if you have questions. Do not expect total recovery. Accept each small step as it comes. You may find that you have to change the way you get along in the world. These changes are called work-arounds or accommodations. Most brain injury therapy is teaching new ways to do things that can not be done the old ways.

Hope you have a good day.