Bruise or broken capillaries?
It is not normal to have a band of grey/brown.purple 2 weeks after your procedure. I would recommend following up with your doctor regularly as this could possibly be a result of ischemia (decreased oxygenation of the tissue due to lack of blood supply) and it may actually lead to increased hair loss in the recipient zone.
Based on your description and choice of words such as "sheet of blood", this is not normal. You need to see your doctor in person for a recheck and examination.
Desperate FUE patient with complicationos
This is a situation which I always advise to go back to your doctor. Most of the complications you discussed are highly unusual and your doctor needs to be concerned because you are. I don't like what you are telling me. Below is an example of complications and poor outcome in a patient who presented my office
Truth is you should really call and go back to the doctor. You will not know if the procedure failed for a good 18 months but at least you should make sure nothing else is going on that could be bad.