I've taken a few tests since my first positive. My FRER with FMU have gotten progressively darker, but I stopped taking them a few days ago because it was getting expensive.

I've also taken some internet cheapies in the afternoon, just for comparison sake. That test also got darker, but the last one two I took (Thursday night and today around 11 AM) look the same to me. Should I be concerned? The test line is still rather dark, just not darker than the test line from four days ago.