What does a faint line mean?

I took one of those cheap pregnancy cassette tests today. I due for AF on Wednesday and today I am 11dpo. I've been feeling gassy, slightly bloated, sore breasts and mood swings, but those are usual AF symptoms for me, except usually I don't get gassy until AF is actually here. I took the cheap cassette test with diluted urine, then forgot about it and didn't check it until half hour or so later, the line is faint but it's a full line instead of looking like a dye run, but I understand that this isn't a reliable result as I know I should read the results with 5 minutes, what shall I do about this result? Could it be positive?