I get headaches several times a week, too (mostly migraines). I added a line on my mood chart to track my migraines so I can tell exactly how many I've been having and what time of day. Before the chart, I'd just report to my doc that it was a couple a week. Turns out, I have headaches about 5 out of 7 days a week. I'm on different meds than you are and I've changed meds in the last year. I have not noticed any change in the migraines from med changes. My bipolar meds don't seem to effect the headaches at all. My pdoc says migraines are common in bipolar patients.

I've noticed that I do seem to get more/worse headaches when my mood is elevated and, especially, when I'm manic.

Hope your headaches get better.