Late period by 7 days :/

So my very on track period is late by 7 days. I've taken 2 tests both negative. I have some mild symptoms (nausea, bloating, tender breasts) should I wait another week. I don't want to pay a visit to my GP if I can help it.

N.B I've not been stressed my diet is well balanced and hasn't changed and I exercise when I can.

Many thanks ladies :)