Help me!!! Opk question

Ok so I tested yesterday and today and got good lines but not positive yet. My BFF said to test again this afternoon as to not miss the positive. When I tested just now there isn't a second line at all?!?! Why??? Did I not hold my urine long enough or did I miss it??? I only went about a hour holding urine and I drank something about 30 mins before I peed :( any help?!?!