ladies please HELP!

Jessica
Help help HELP! I posted some vfl cheap test phtotos the other day and got great responses! I took the top test last night and got a BFP but this morning with a different test (on the bottom) I got a BFN. I am 15 dpo and 1 day late. No period sypmtoms, just very moody and a tight feeling across my lower abdomen. Thoughts?