Looks like your tests came out very clear. CD 15 almost looks like a positive to me too, but CD 16 is clearly positive. With my answer tests, I only got one definite positive on CD 14, 24 hours later I got a negative. I know though if we aren't PG this month, I know now what to expect and how to do it!
Cheers to BD and BFP PG tests in the near future!!