Today I passed out at the gym. I lifted some weights from the floor and I think the sudden blood pressure drop made me pass out. I'm not exactly sure, however. I don't know if I hit my head but I definitely had a headache afterwards, and I highly suspect I have a concussion.
I went to the doctor since I was going to take a vaccine today anyway (for the US trip) and she looked at my blood pressure, bpm and breath and said I was fine. I'm not entirely sure, though, to be honest - it definitely feels like I have a concussion, since I had a massive headache, was very emotionally volatile and felt extremely tired. I think I'll be fine now, though, since most of that has gone away. It's been 8 hours since it happened.
Anyway, the doctor gave me an ECG monitor because she said my heart rate was too fast. We'll see if that turns up anything or if it's just a mild annoyance for 24 hours :)