Letrozole!!

Amanda
So this is for all the woman who have been on letrozole and the trigger shot. I did the shot on April 1st. I am 13 DPO. I was told not to take a test until the 17th. Well I couldn't wait so I took one on Tuesday morning and it was BFP! Well I asked me Drs office and they told me not to test until Sunday because it could be a false positive. Well I've been taking tests every morning and I've been getting BFP! I also took one this afternoon and it was BFP. 
Has anyone else experienced this and had it actually be a BFP or was it a false positive even though the Drs office said the drugs is only in your system for 10-12 days?