Before you go for something like HBOT, try these for frequent headaches:
1. Cutting out coffee for a few weeks completely - it's not necessarily the caffeine but can be hormones or other in the coffee.
2. Try and get a prescription for amitriptyline - I had severe migraines for months and was prescribed it as it can "turn them off". It did, and as a side effect made me way less grumpy and anxious. In the meantime, I stopped drinking coffee, I then came off amitriptyline and then about 6 months later started drinking coffee again and the migraines came back.
I've also done HBOT as I had Bell's Palsy and it worked amazingly well in helping me recover from that. For anything else, do your research on NIH, not here.
Good luck.