What is it about this time of year???

Well here it is that time of year and Sweet Pea just couldn't resist having an episode. So it was just about bedtime last night and the kids were playing upstairs. When we called them downstairs apparently Sweet Pea wasn't going fast enough for Little Man so he kind of plowed her down the last few steps and she took a tumble. Of course there were a great many tears shed, a swollen and bleeding lip and a strange desire to check her heart rate. I listened to her by way of ear on chest and I could hear both parts of the beat but it sounded kind of "funny". So I grabbed the stethoscope and again I could hear both parts but it just sounded "funny". Then we grab the handy dandy pulseox we have laying in her drawer "just in case" and hook her up...159, 160, 158 no problem things are fine. Just as I go to unhook her she jumps...259, 258, 240, 256...so we begin the process of trying to convert her ourselves all while dialing the EP. We tried to get her plug her nose and swollaw (not easy with an almost 3 year old), I take her potty as I'm also trying to ring the dr. on the phone and she's still high. He suggests the ice to face the trick and Daddy had thankfully been coming with those freezer packs you have on hand for boo boo's and we smother her with those for a brief time. We're not sure if it was the potty trick or the ice pack trick but she converted and all was right with the world. Her EP said she is at the very bottom for dosing on the Atenolol and he doesn't want to move the dose. He feels this was just a freak break through episode due to the trauma of the fall and just keep an eye on her which we of course did like a hawk. Will the fun ever end??? What is it about this time of year?