is this sinus?

Hi - I was wondering if you could help me with something - I can get sinus headaches and pressure, Im used to this....especially when it gets cold outside. My mother and grandmother had this, and so does my son. We usually take over the counter stuff for this, sometimes it helps, sometimes it doesn't....pain in the neck!
Now, yesterday, I had such pressure behind my eyes, I thought my eyes would pop out of my head, and I got pretty dizzy, for a few hours. I laid down, and eventually, the dizziness subsided.(the pressure behind the eyes still came and went)....now, this morning upon getting out of bed, I felt "weird" in the head, and lightheaded...not really "dizzy", just a little off balance. The pressure behind the eyes was still there, but had diminished significantly. Sometimes I almost feel as though it affects my eyesight, not badly, but to some degree. I can still see fine, but my eyes get extremley dry, and they feel "thick", that's the best way I can explain it. Also, it seems sometimes as though I'm looking through some kind of "screen" when this happens.....it's weird. I don't know if this is all sinus, or not....CAN ANYONE HELP??????????????????????????????????????????????????????????????