Hello Colette, and Welcome to this group. The 7 day course of steroid tablets are there to reduce inflammation in your lungs, so the inhalers can keep it at bay normally.
The weight gain, I am sorry to say, is normal with steroid medication, so I tend to eat little but often to stop me snacking out on the 'nicer' things like crisps etc...the things we do to keep out figures eh boys n girls !!
Again, panic attacks are normal, as your blood oxygen has probably dipped in level and your body is saying that something is wrong... recognising that you are having a panic attack... find an object or a spot on the wall, look at it as a point of focus, and try to slow your breathing down by breathing in, counting to 2 then slowly breathing out and repeat. When having a panic attack breathing becomes rapid and shallow, so more carbon dioxide is breathed out and less oxygen breathed in. Slowing your breathing rate down gives your lungs, heart and brain to re-synch so more oxygen can get into your system.
As for smoking... you know what to do ...
Don't think about time of life etc... just keep active as you can. The thing with COPD that if you do a little more each day then things get easier i.e. the more you do, the more you can do ( seems a funny expression, but it is true ) so whenever you walk, pick a spot ahead and as a reward for reaching that spot and being mildly breathless have a 10 sec breather, then pick another spot to reach etc. Potter about in the house etc, just be as active as you can be. Remember that you rule it, it doesn't rule you.
Ask your nurse if you need additional meds like Singulair and Mucodyne, and also ask if there are any pulmonary rehabilitation classes in your area. Pulmonary rehab is a godsend, as they give you light aerobic exercises, breathing techniques, relaxation techniques, how to take inhaler meds, different types of meds and a whole lot of useful stuff. And it helps to get out and discuss your experiences with COPD and find out how other people cope with things.
I take it that from the things you have put here that you live in Britain...And dont worry, I have a baby's chest, it never goes anywhere without a rattle.
Hope this helps Colette.