The other day I sad in a chair reading something on my phone. When I got up from the chair i got dizzy so I decided just to stand still till my head was clear but the next thing I was able to register while it was happening was that I had fell back over. It is maybe worth mentioning that it was an unusually hot day, and I had not slept for like 30 hours. Can this be due to the 2 previously mentioned factors or why do you think this happened? -Benjamin
Feeling dizzy while getting up from chair seems postural hypotension. Postural hypotension. Postural hypotension is more common in conditions like hot weather, fever, during micturition/straining for stool.