Sorry to hear about how you've been feeling. As someone who has suffered from depression and anxiety, I can relate to what you're going through right now - you're not alone!
In terms of coping, there are two main things to address to lay the foundation for recovery. Firstly, make sure that you are looking after yourself physically well - being physically well (keeping clean, sleeping well, eating properly etc) provides the foundation from which you can explore and tackle your mental health issues much better!
Secondly, discovering what things in your life you can control and what you can't, and working to make those you can control more secure. For example, you can't control your health (although you can influence it), but you can control how you express your feelings (counsellor, diary etc). You've mentioned that you feel you have lost control - taking back control on small things that are controllable helps you to regain the steering wheel of your life!x
Much love <3