Hello beautiful people!

I've been working out for quite some time now but only recently I've been experiencing dizziness during cardio workouts. During the usual 10 second pauses between cardio, my head starts to spin and I feel really uneasy to the point I need to sit down. This has never happened to me before and I'm still looking for the cause of this feeling. Dehydration and malnutrition are definitely not the problem. Thank you in advance for any tips !!