Too early for a blood test?

Corie

I’m 7 days late for AF, pressure in my lower abdomen, bouts of nausea and headaches. All urine tests come up negative, so I went to the doctor for a blood test and that came up negative. They’re thinking it’s a UTI but I’ve had those and have none of those symptoms. HELP! Anyone else have a negative blood test, but was actually pregnant?