My moderate TBI was 32 years ago. My headache only lasted a week so best to check with a neurologist on ways to manage that. I was working and writing my PhD dissertation at the time, so recovery was my year from hell (1.5 years to get to 90%). Pacing onself and napping so you don't hit the extreme fatigue is important. If you have an office, close the door and take a short nap. Good that you are in speech therapy. The brain does rewire, but it takes a long time and is a bit like a staircase with steps up, plateaus, and then down as the brain heals. Single focus is important while healing; break jobs into easier pieces rather than trying to multitask. I still do crosswords, suduko, and other games and I keep learning (my version of the brain as a muscle). Stress is very hard, and difficult to avoid, but find whatever escapes that you can. Let us know how you are doing and your healing progresses.