How To Overcome Feeling Of Fear In Relation To Job?

I was signed off for one week by my doctor (I could tell he was reluctant to) after I described the level of stress I was experiencing at work and some at home. He asked what I would do and I said would try and relax and take gentle exercise. The past week I've panicked about returning to work and my home situation has escalated where I feel out of control. I feel unable to cope with normal every day demands and am finding myself having rages at my husband and having little patience for anyone and everyone. I feel physically sick at the thought of returning to my job which is emotionally demanding but I can't cope around my husband as we have been fighting fir a year. We just started couples counselling yesterday, but still fought this morning. I've also had 3 assessment sessions for psychotherapy in the last few weeks and am due another assessment in two weeks time. My doctor prescribed me sertraline a few months ago and told me to decrease to half a tablet when I found I was constantly tired. He then told me to go back up to one tablet as if last week after signing me off for one week., but the tablets have made me constantly tired again.

I'm sure the doctor has done everything right in terms of medication and referring me for treatment, but I cant face going back to my job and feel like I will panic and have rages when I return. I also feel a sense of detachment from my job. I am due to see my doctor again today, but don't know what to do. I have a huge fear of returning to my job, when I don't feel ready to cope with anything. I've not been able to relax at all and fear I am going to lose the plot completely. I gave no idea how to convey this to my doctor or what to do to get rid of this feeling or cope of everything being too much.