Panic attacks and blackouts

Any practical advice on how to overcome them?

I was recently describing some of my problems with a mental health team and they diagnosed it as a panic attack.

Many years ago, when I was 12, I think, I was out buying shoes and I walked into one of these small independent shoe shops where there is a narrow stair case to get to the men's shoes floor.  And I lost consciousness. I remembered the distinctive smell of shoes and then my legs to weaker and head started feeling as if my brain was collapsing and I lost consciousness.

A few days later I had a similar problem walking into other shoe stores. It was always the same, smell of shoes in a confined space, legs weakening and head spinning and a blackness overcoming my mind.  Stopping and retreating reversed the effects.

Once I collapsed in a city centre boots store with no warning.  I just came to, sitting in a chair being asked if I was ok and did I want a drink of water.  I don't even remember losing consciousness.

In One place I was working at, I couldn't walk into the main canteen, I could hear everyone talking and having a good time, but I couldn't walk through the door.  The closer I got the weaker my legs and a black cloud enveloping my mind.  It took me repeated attempts over a month before i could walk through the door.  People thought I was aloof and antisocial.

Walking alone into pubs caused me similar effects.  It's only in the last five years that I can walk through a pub door and order a drink and a meal.

I live in constant fear that I will have a blackout in public.