I think most people show the pattern of very high systolic during and immediately after strenuaous exercise and then a rapid fall in bothe pulse and pressure. These are the main pairs of mechanisms (hart-rate and pressure) to deliver extra nutrients to the muscles when they need it. Even immediately after excercise there's a lot of wastes that have to be removed so the furious pace continues.
I WISH I could get a decent BP reading when I have my heart rate 130-140, my practical maximum, on the stationary bike but the motion or noise or whatever makes my BP tester go rammy and give me truly goofy readings. Best I can do is jump off the bike, lie on the floor, and take my BP immediately. Of course, EVERRYONE in the gym thinks I've just had a heart attack or gone bonkers.
That first reading is always a DOOZY but it gets down pretty fast...and within 1/2 hour will go to the lowast readings I ever get.
You aren't taking any BP meds, right?