Fading test results

Last Thursday I got a faint positive on a First Response. Took tests every day which were all positive and mostly increasing in strength. However this morning when I took the test (FMU) it looked almost as faint as the first one I took last Thursday. Today I am one day late on my period. Have been madly googling, of course it looks like this signals a chemical pregnancy and given my age (42) quite likely. I just want my period to come so I can start again if that is the case. I now have to travel for work for 3 days so I just have to wait it out before I see a doctor for blood tests. I already have 2 kids, 4 and 6, just never shook the desire to have a 3rd. Maybe I was being greedy.