Why do intrusive failure thoughts destroy relaxation in Metta?

As soon as I reach a high level of relaxation, I start having intrusive thoughts concerning career failure or personal inadequacy. These considerations appear to destroy harmony. Is it some kind of self-sabotaging psychologically, or is my psyche associating relaxation with weakness? And it is my overthinking that tries to deconstruct the failure. My name is Nisha, DOB 15th May 1990. Time: 11:50 AM. Location: Gurgaon.