How do i relive sinus/nasal pain from a blocked sneeze? it takes between a few minutes to a couple hours for the pressure to come out, why is that?

Swelling: Likely part of what made you sneeze is swelling in your nasal passages / sinuses. So when you stifled the sneeze, it increased pressure in sinus(-es) which is trapped there temporarily, causing discomfort. Could try pseudoephedrine (from pharmacist) or nasal spray like Afrin (for BRIEF use--2-3 days max) to reduce swelling. If continues, see Dr for nasal steroid or antihistamine recc., depending.