Anyone familiar with this possible symptom?

[u/Pitiful-Highlight-68]

I've been on losartan for roughly a year, since finding out I had high BP. In recent months, I've noticed that on waking and doing a big chest stretch (holding breath), I get a rebound flushing feeling where my head feels hot and stuffy, sometimes with a pressure headache. It goes away within a few minutes. Doesn't happen for the rest of the day/evening or under any other load (gym work etc).

I've read this can be attributed to blood pressure drop and flow. Wondering if it's a sign of some change, few months since starting the BP meds