Sick sick sick

On July 1 I got supppppper nauseous and was up till 5am cuz of it and had bad diarrhea. On August 22 I got nauseous again, used the bathroom 2 times and had soft stools but nausea went away after that and went to sleep. Last night I got nauseous again and had soft stools was nauseous for a few hours and then went to sleep. I’ve also been having brain fog and tons of headaches and am always tired. Nausea only occurs at night. I have no idea what’s going on. I just booked a doctors appt but could only get in 2 weeks from now.