“Primulot query?”

Good day,

Here's my history - the first day of my last cycle was 20 June. Menstruation lasted 5 days. On Cycle Day 21 I then had a progesterone blood test and my OBGYN advised that I did not ovulate this cycle. He then started me on x1 mg primulot tablets x3 times per day for 10 days. I am currently on day 6. Following which I am supposed to menstruate and then start my first round of Clomid
I have not been feeling myself and also read that primolut should not be taken while pregnant as it can cause abnormalities/defects so for peace of mind I took a pregnancy test which looks to me like its a faint positive (see image attached). I will need to wait until tomorrow to use first morning urine for a more accurate reading.
So my question is, is it possible that my CD21 blood test had inaccurate readings? But more cause for concern, if I am indeed pregnant, will it be a viable pregnancy if I have taken the primulot for 6 days (approx. 18 tablets)

Lastly, does Primulot cause a false positive on a pregnancy test?

I will of course schedule an appointment with my OBGYN if my pregnancy test comes back positive again tomorrow morning.

I look forward to your feedback.

Thank you.