Hm my problem seem to be similar to some of the things people wrote.
I had a tooth extraction last week on Thursday and they told me all the risks and one of them was that sinus can be open. They didn't say if this actually happened after the extraction. Few days later I felt unwell, headache, left side where tooth was removed was pulsing badly, I felt weak and sick. That just got worse until one night I couldn't sleep. I went back to dentist and they removed the stitches to see better and said there is no infection. I told them that when i was rinsing my mouth the water was coming out my nose but they didn't seem to think that's odd. They put something antibacterial in my tooth and said it will fall and if I have pain in few days to go back. On next day something very stinky started coming out my nose and I felt horrible. This morning I woke up with horrible headache and the antibacterial thing fell out. The moment I rinsed my mouth with salty water everything came out my nose. Now I'm about to visit my dentist again, hopefully get some help as this is this is the worse experience in my life. I can't sleep, eat or do my daily routines as I have no power. if anyone has some advice, that would be great.