Has anyone else started looking at smartwatch data around their migraines?

Random one for the group. I bought a Garmin earlier this year for completely unrelated reasons (running, briefly, before I gave up on that). But I've been checking the watch app on the morning after a migraine, just out of curiosity, and I keep noticing the same thing. My HRV was always low the day before. Not always by a lot, but always.

I'm not a doctor or anything close to one. I'm just a person with chronic migraines staring at graphs trying to find a thread. Has anyone else here noticed something similar in their own data? HRV, sleep stages, stress score, body temperature, any of it? Or is this just me seeing patterns where there aren't any?

I've tried a couple of small things on the days my HRV looked off, going to bed earlier, skipping coffee, drinking more water. Honestly I don't know yet whether any of it helped or whether I just had a quieter week. Would love to hear what other people have done with this kind of data, if anything. Or whether I'm wasting my time.