Hi Op, many years ago l suffered a bout of severe anxiety, after 3 failed pregnancies and a stay in hospital. this is what helped me.
Practical changes,
mornings were horrible so l immediately, did 10 minutes of Yoga breathing,( google it) in bed, to control the racing thoughts,then getting ready can you listen to a mindfullness podcast? or a positive thinking meditation? I used a yoga TV program, as l found it relaxing. Really focus on it to stop thinking negatively.
On the way to work repeat positive messages to yourself relentlessly,( in your head if on public transport) ie 'l will stay calm and have a productive morning'
sounds silly but again it focusses you on the message and stops the mad thoughts taking over.
On arrival at work, sit down take 3 deep breaths and say in your head, l am going to do these three things in the next hour, write them down if necessary, and put a line thru when done.
Once done get up for a drink of water, and mentally tell yourself well done. Sit down and repeat for the next hour, and so on, practice the discipline of one hour at a time, don't think past that.
Remember to praise yourself for each small step achieved.
Plan healthy meals whether you want to eat or not, as erratic blood sugar does not help your mood to be stable.
Going home was tough for me so l used to immediately get on the floor in front of the tv, and follow a slow yoga session, it requires enough mental effort to not allow your brain to go off at a tangent, but is both physically and mentally relaxing.(and you don't have to be fit !) If you cannot get into yoga, is there some other form of exercise you love that you can do regularly?
Mentally what was the ultimate turning point for me was the realisation that a) no one else can get me feeling better, l have to work daily on my thoughts to turn them around.
b) l am not on this earth to take on the world, sometimes just getting quietly through the day is enough ( l used to be the person who took full responsibility for everyone and everything, hence l crashed)
c) learning that l have limits and respecting them (now if l am tired l take a nap without guilt)
Lastly (sorry for the epic post)
Remind yourself,
you will not die from anxiety however bad you feel
thoughts can be changed
you are good enough,