Looks like an obvious bfp but.....

Lisa
Ok. So yesterday morning I took a first signal Walmart cheapie and as soon as it finished it looked like a very faint positive. So I laid it on my counter and walked off, mind you it showed faint bfp within the time frame, came back and looked again and bright dark positive. I mean the darkest bfp I've ever seen on a First signal test. But what is confusing me and making think twice about it is I took a first response this morning and it was negative... I'm sure I'm not pregnant and I'm just clinging to hope. Bc I feel like it would have showed positive on the first response. Any advice or thoughts would be greatly appreciated. Thanks so much