Please Help

Ruby
My period ended sunday...  my fertile days were towards the end of this week. I took an ovulation strip test Wednesday and I had two blue lines for positive and same for Thursday but when I input them in glow it change my fertile days to Monday - Friday... did I miss my chance??? Can you only get pregnant on fertile days? Which day is the day you Ovulate? Took a test today it the line was super faint... please help.