Hi again,
Just in case anyone else has the same question, I thought I would update this thread with what I think is the answer: the tests were faulty. I've done 2 more tests using a different brand and they were both negative. I don't have the blood results yet but I fully expect it to be negative too.
The Better Health channel website (Pregnancy testing) says false positives could be caused by:
Detergents in the collection cup. I used new specimen jars for both bfps so I doubt this was an issue.
Reading the test after the time limit: both bfps came up immediately.
Evap line etc: both bfps were pink and the same width as the control line.
Chemical pregnancy: I've had chemicals before and always had a very heavy period within days of the bfp. It's now 6 days later and no AF.
So I really think the tests were faulty.
I had my implanon out three months ago. I had no periods for the 1.5 yrs it was in and haven't had one since taking it out. Think I'll stop wasting money on hpts and buy some opks instead.
If anyone has any other ideas I'd love to hear them. Thanks.