I'm no expert and have never taken temps before but i hope the slight lines you see are the real thing. Get some more and pee away and see what becomes of it... your pee may become a little diluted though It's a long few days but hopefully over the next day or so the line will become more definate.

FWIW I think i have mostly used the crystal clear tests (not sure how they rate) and my lines have been fairly faint but definately there.

Good luck, thinking of you xo