I would say, accept the negative result, however re-test in a few days if your period still hasnt returned.
I'd wait another week to get a blood test if I were you.
I'm having a similar issue, i've read that gold digital test detect 100 miu of hcg in urine which aren't nearly as sensitive as some of the other brands.....First Response(non-digital) are supposed to detect like 25 miu of hcg of urine....My last period was on Apirl 3rd and i'm 9 days late and I've got symptoms so i've got no idea whts going on....!