O test

My o test was a faint line on saturday afternoon then I tested in the evening and the line got lighter. I tested yesterday twice and the line hardly showed. Less then the first time. I haven't tested yet but glow says it's my peak fertility day. I'm confused and I'm worried I ovulated pre 12cd... which is very early. Maybe I'll ovulate later? Just so confused and dissapointed due to the first faint line.