Weird feeling in head immediately after taking big hit?

Anyone else ever notice that warm feeling in your upper sinus area, and forehead that usually happens as soon as u take a big hit? why is this happenning? One of my friends told me its the thc absorbing into your bloodstream from your sinuses, so you can feel the high starting in your head. Another friend told me it was from oxygen deprivation. Now i dont think oxygen deprivation is likely because no matter what im smoking from i tend to take a huge breath of fresh air to suck that smoke down into my lungs anyway, and Im sure its plenty of oxygen for one breath. Opinions?

 

no, the feeling lasts for about 30s after i usually take the hit, I didnt exactly mean warm, kinda like a feeling of pressure in your head. Usually between right between your eyes and in your upper sinuses. And its not me just being high because i get this feeling before i even get high, it takes about 10 mins for me to get high after i smoke.

 

so pretty much it does have something to do with oxygen deprivation or at least the body sensing it, then sending more blood to wherever needs it the most. so i guess holding in the hit could cause my body to send more blood to my brain, and Im feeling this sensation from the change in blood pressure and or facial muscles relaxing themselves. seems like the best possible explanation now that i read that page.

 

nice thanks for clearin this up, ive always been curious about this.