Why when i blow my nose or hold my nose do i have so much pressure build in my ears like im on a airplane is this normal could it cause vertigo?

Eustachian tube: You are suffering with eustachian tube dysfunction. The eustachian tube connects the space behind the eardrum to the back inside of the nose. Sinus issues (allergy, infection, etc) can cause inflammation of the et so when you blow your nose, pressure builds up. Treat with otc saline sinus rinse, antihistamines/ decongestants, etc. Usually a benign condition but see a doc if severe or lingers.