I would definitely be excited!!
I've always heard that there's "no such thing as a false positive" (since it detects a hormone, and if that hormone isn't there it can't detect it). I would go buy a few more HPTs and keep taking them until you get into the dr lol
I was on Metformin and many many times missed periods because of the PCOS and I would test and it was always a BFN! So I don't think the Met or the PCOS will cause a false positive
Let us know!!!!