Feels like a vein pulsing in ear canal, occurs for a few seconds when burp/hiccup, i can't hear it i just feel it pulse like heart beat uncomfortable.

Otitis w effusion: You may have otitis media w effusion (also called serous otitis) where normal ear drainage & pressure-equalizing systems are blocked. Tho antihistamines or decongestants may relieve some congestion, they are not proven cures. Generally, this clears on its own in 10-12 weeks. See your clinician or ear-nose-throat specialist if worsens, doesn't get better, or you have concerns. Hope that helps.