TTC - bfn but no period

Jess

So, myself and my partner have been trying to conceive for 14 months now, the last few months my periods have been every 28 days lasting for 4... I was due on the 15th Feb! Still no sign of AF, I have been feeling nauseous, my boobs are tender and I’m so tired all of the time. I done a cheap test this morning, but it came back negative! I’m so confused and upset! Can anyone shed any light or have similar experiences where you actually were pregnant with a bfn test?