If the shed is dry and used on a regular basis, I don't see any big problem.
Problem comes if the shed is just used as a store and left for months on end with no heating, the damp will set in and equipment will suffer.
JimB
On edit:
PS, don't feel inadequate, I started in a shed many years ago when I was 13/14.
In the intervening years I have gone through various lesser accommodations and now have a room which at one end has all my electronic and radio stuff, and at the other end has my "office" for business.
I also have a loft full of stuff, and the garage is my mechanical workshop for when I want to do any "chassis bashing" or other odd mechanical bits to support the radio/electronics.
Just do the best you can with in the facilities and £££ available to you, and you will make progress.
JimB