Weird and confused

Ok so the start of this month I bled a little not like my normal period at all in 4 day I only went threw 7 tampons I normally go threw about 10-15 a day the first 3days. So now it’s the 19th and when I went to go pee I wiped and it has a red tint to it not like a lot but enough I can see with my bad eyes. Also sex has been painful for 2 days Iv never felt that kind of pressure and knife like pain before also when I sit it feels the same way with pressure and stabbing pain that started about 4 days ago