Mustard1, welcome to MM
It is a good idea to switch to transdermal HRT as time goes on - often fewer side effects with transdermal and can also deliver the hormones more efficiently. I do think that it's not just hormones that trigger the low mood and anxiety - I personally think this is all part of the ageing process for many of us. I even see it in my husband - he is so much more anxious these days. Hopefully the change of HRT will help but you do also need to do more relaxation techniques, get out for brisk walks to clear the head and find strategies to cope when anxiety strikes. I wake some mornings feeling so despondent and awful, so I force myself to plan specific things that will occupy my mind and make me feel good. This is all part of the CBT that I have learned over the years. As CKLD has mentioned, eating regularly to avoid low blood sugar is vital. If you are taking ADs, then I'd have these reviewed as well.
DG x