Hi Charlotte
Like the others said, that is a good loss and I am sure you will see the difference next week. Dont give up because of it!
I will be having a period for 3-6 months due to an op I had....so, think yourself lucky ;-) I dont know what my WI will be this week, but I just have to keep looking forward.
Main thing is to remain positive and think it will pass and by this time next week you will be shouting from the rooftops as you will have had a good loss!
Take care