Suggest Treatment For Dizziness & Muffled Hearing

within the last 3 months there has been two occasions on which this has happened, I will start by feeling a little sick in my stomach, this then gradually gets worse and worse, as i go to sit down or to the toilet i become extremely dizzy, and I can t see clearly (Speckly vision and blackspots). The worst part is my hearing and everythings muffled. feels like im underwater or a pillow over my head. on the first occasion i was sick after this but the second time i was not although i felt very close. From what i remember I had a normal diet that day and had sugar intake with a considerable amount of water. Im confused about what the problem could be?