BFP now a BFN? HELP

Kristina
Last Sunday I got my first vfl, tested everyday after that and watched it get darker. On Wednesday I took a digital and it was a BFP and I've been feeling symptoms.
 Today I took another test and it was very clearly a BFN, almost a week after my positive. I feel the same as I did last week but I just don't know what this could mean. I've already had 3 miscarriages in 12 months, 1 chemical, 2 at 10 weeks 😕 really hoping this isn't gonna be chemical.. I dropped the test on the floor before taking it if that would affect the results at all?