Erica, I had Pericarditis twice, many years ago. The first one I had only bed rest, and recovered in a few weeks. The second time they gave me Prednisone, and it was a bad idea. I felt like I was manic, crazy, pounded walls. Not a good idea. Bed rest was the best way to get over it for me.
It sounds like R-E-S-T is on the ticket for you, in spite of your need to do things and be active.
My platelets are twice normal, but that's "normal" almost, for me. That's not from reactive thrombocytosis but from Polycythemia Vera which I added to my 'charm bracelet" 8 or 9 years ago. I use aspirin powdered and rubbed into my skin (equiv. of baby aspirin a day or one whole uncoated aspirin over four days). I proved the aspirin goes through the skin when I tried someone's idea to take a whole aspirin daily in this manner--I got a nose bleed, nurse told me to stop the excess aspirin. I powder the aspirin myself in a bowl with the handle of a table knife.