Heart rate spikes

Okay, so I’m a 28 year old female. I have the SE Apple Watch. I’ve noticed for a while I’ve had random heart rate spikes. One was 210bpm after a workout.. the rest have been for no reason. I brought it up to the cardiologist, of course he says “get a new watch, if these were real you’d pass out or this or that”. During the stress test I compared my watch to their machine and it matched spot on pretty much. Now, that doesn’t mean my watch still couldn’t be giving some false readings here and there. All my tests came back normal including the holter. I would like to think these high spikes are just glitches, but idk what to think, it’s freaky. At work last night I was just chilling, later on in the night I go look at my heart rate details.. 194bpm it said. I felt completely fine during that time. While I was just doing mild work, not out of breath or anything. HUH?? Then back down to 76bpm. I don’t know anyone personally who experiences this! It’s driving me nuts!