Hi @Mjn88. Also sorry to see you didn't get a reply here sooner.
I live with both anxiety and depression (and ptsd). It can be very difficult to manage sometimes. It can feel a bit like being all over the place for me, or up and down as you said. Sometimes it feels to me like being wide awake but completely exhausted, or having lots of energy but not knowing where best to put it. I describe it as a rollercoaster and it can be wild.
Do you have much in the way of support? As @appleblossom mentioned, it can really help to have a support team to talk with and work through things with.
This thread
here has some great ideas for coping strategies if you're interested. There are some distractions, grounding activities and helpful bits and pieces I find can be useful during different experiences (of which there can be many when you live with anxiety and depression).
Best wishes