positive HPT b/c of trigger shot?

I am in my first round of IVF and took my 10000 IU HCG shot 12 days ago (10/31). I had a positive HPT this morning and negative this afternoon. The positive was first thing this morning and detected 50 mIU of HCG. This afternoon's test needs 100 mIU of HCG. Is it possible there was a little of the HCG shot left over this morning for a false positive?

[kindergal]

I am not sure...but I think I have heard the trigger shot can stay in your system for 14 days.....So maybe test again in a couple of days.....

[tina1111]

Usually the trigger is out of your system in 10 days. That being said, USUALLY is the key. There was a poster a few wks ago that was still testing pos from trigger 13 days after. I hope it's the real deal for you.

[SLMS]

unfortunetly, the same test that was positive yesterday is negative this morning. It must have been some HCG left over....I know there is still a chance but it doesn't look very promising. Thanks for your answers!