I didn't get my digital positive until I hit over 25 for my HCG levels. I would give it a day and test again! If you got a pretty obvious positive on FRER you're probably not too far away!
I got a positive very early on. Just had a feeling! Then for a whole week I had all digital negatives even when using first morning urine. It took until I was a day late to finally get a positive again! Try to relax and wait until your missed period, or a few days after! Good luck!
Re: Update- BFP... Well, maybe not
It's a boy! Grow baby, grow! EDD: 4/22/2016