My mother has recently completed her social work degree, and similarly struggled with anxiety during her first training year (difficulty sleeping, feeling worthless, constant stress, bouts of crying). She went to the doctor and got prescribed a drug that really helped her and has reduced her anxiety levels completely. It's a common thing and nothing to be ashamed of. Go to the doctors! Anxiety is the same as any other illness. Teaching is incredibly stressful and the government don't make it any easier. Out of all the professions, this job seems to have one of the smallest support networks for mental health and the biggest workload/ stressors. Seek help! You deserve it! Hope all goes well :-)