Faint and then negative

Okay so I'm now only 11dpo. Yesterday evening and this morning I got a first response with te absolute faintest second lines possible. This afternoon I took a first response digital and a clear blue. They were both negative ?. I noticed that the urine I used for the negatives though was significantly lighter so I'm guessing it was less strong. Anyone else experiences this? I don't know whether to feel it's just theburine wasn't strong? I've always kind of thought if the hormone is there, it's either there or it's not.