WEIRD REFLUX ON THE NOSE

This is not related to pregnancy or ttc. I am just curious. I've been experiencing something weird everytime I bend down my body into a 45 degree angle like if I try to pick up something on the floor. Something is like refluxing but not on my mouth or throat but on my nose. I don't know how to express how it feels like something is rushing into my nose. There is no discharge or anything from it, it just feels uncomfortable like blood is rushing or something. It does not happen to me. I wonder what it is. I can't stay bent down for 3 sec or more.