GP is primary care so general not a specialist. This means that they would need to refer you to secondary care e.g. hospital or psychology, for treatment and diagnosis in general.
However, the goal is getting help as psychology isn't necessary a permanent thing, especially if it is linked to covid and lockdown. In other words, you can recover.
It depends where you live, but there may be self help local services that you can go to by yourself ie self refer without GP.
There are internet resources.
Lots of self help books which are helpful (such as the "Overcoming" series e.g. Overcoming Anxiety, Overcoming Depression, etc).
There are health shops who may have practitioners there or advice e.g counselling, hypnotherapy.
There are groups you can go to if you don't mind being in a group. You don't necessarily have to talk and they may have ideas of where to go for help.
There are meditation classes and relaxation classes everywhere (plus online e.g. youtube Jason Stephenson, positive affirmations, guided things).
You can also do yoga, Tai Chi or Chi Kung/Qi Gong classes and groups (or see online like youtube or books). They are all forms of meditation and also overall wellbeing holistically.
A book I like is Tara Ward Healing Handbook (releasing old emotions and trauma in safe ways). Pick and choose which technique as some you may not like, some might be great. Repeat as much as you want.
There are other workbook practical books too.
Basically, learning and practicing calm as much as possible. Doesn't have to be all the time, just learn the habbit and skill.
Plus you have GP, NHS specialists, and private specialists you can pay to see.