"Urgent blood test done at Newark hospital"

Visited GP who sent me to Newark hospital for an urgent blood test, query DVT, this year, having not heard anything I tried to call my GP to be told he was not available and to phone the next day. When I phoned I was informed my blood sample had been rejected and needed to be redone. Appointment for blood test to be repeated was at the GP's with some pressure applied to get this, during this appointment I was advised that my previous blood test had been done using the wrong bottle so hence was rejected. I understand mistakes happen, however would expect measures to be in place to rectify them, why was my GP or myself not alerted to the fact that the blood sample needed to be repeated. Friday evening I am told to attend Eastward Day hospital on a Monday for tests - due to abnormal results - and if I suffer chest pains or SOB prior to this then I should present at hospital, I feel this is not acceptable and that there should be a system in place to avoid such oversights occurring, not sure what the out come for me will be.