Question: hi, i have an issue with being randomly light headed. i am 27 years old 9 male and very healthy for the most part.
I can run for 15 minutes and walk another hour then sit down and sometimes out of nowhere i get this light headed feeling that im floating. no other symptom no pain no dizziness no blurry vision nothing. usually it goes away within 5-10 seconds and back to normal. happens when i stand sometimes or after i sit. its so inconsistent that i cant pin point a trigger. i work 8 hours a day and sometimes ill get this 6 times in a work day or others 1 time and sometimes like today,
it didnt happen at all at work and when i got home i was talking to my mom sitting down i looked down at my phone looked up and BOOM light headed 10 seconds later back to normal and hasn't happened again today. its not always when i move my head sometimes i can be sitting down watching a movie and i turn my eye to see my phone and bam. when i workout it happens a lot with weight training. ill get this floaty feeling between most sets when i do lifting but never happens when i go cycling for 30 minutes.
its seriously annoying and idk what to do.

1) just feels like im floating like i zoom out and its hard for me to focus my eyes onto something but i dont get dizzy the room doesn't spin i dont get blurry eyed or anything it usually goes away 5-10 seconds.
2) Happens at any random time. some days worse some better. yesterday it happened 6 times while i was on my compuuter playing games today 2 times while i was helping my aunt move out of her house.
one day at work it happened like 8 times and then the next day i was at home relaxing watching movies and it only happened once the entire day
3) none what so ever. i try my best to eat healthy i dont smoke or drink

I've been thinking really hard about your second question. (mental stress/anxiety).
Although it happens randomly, it doesn't ever happen during the first hours of the morning while im calm and just woken up, the entire middle of the day is where it happens and at night before bed almost never.
the way it seams to happen 90% of the time is when i turn my head, for example sitting down talking to my friends someone came through the door i looked left than back to my right and it hit me. The other day i was playing racket ball and it happened one time while i was running after the ball i had to get down low get it behind a bush and when i got up turned around it hit me.
Another time i was playing a very intense competitive game with my friends and during that hour it happened like 6 times. but what messes with me is that i played again last night and it didnt happen once during gaming.

i dont know if its relevant but im addicted to coffee. i drink a strong double shot every morning and almost always have another caffeine intake during the day .