to be honest, Id leave it a further week or so and test again. You may have a bug or be stressed or be pregnant and the GP wont be able to do much about any of them immediately.
Your short period and going off food could be signs of any of them.
I once went without a period for 5 months for no apparent reason and went to see GP after 2 months. I was told to keep testing and eventually id get either a positive result of my period. In the meantime i was told to act as if i was pregnant and avoid anything harmful in pregnancy. Turns out i wasnt pregnant, never found the cause
Wait a week, test again, and avoid alcohol, cigarettes, pate, soft cheeses, asprin, runny eggs, and all the other things that are to be steered clear of.
I hope you get the result you want :)