Gentle start to training

So a couple of weeks of getting into the groove, writing my mental health blog and at last I felt ready to do something. I have had my MRI scan on my knee and despite it being very panful and stopping me from doing any real exercise for the last 6 months, the doctors are saying its not a bad tear and that a series of injections should fix things. To be honest I am not sure I am happy about that, I need this fixing once and for all and although the injections could see results virtually straight away, which would mean I would be able to start going for good walks and maybe even a bit of jogging (and getting back to the wonderful weekly parkrun. But if it doesn’t work they have to wait 5 months before they can operate!
Anyway although the injections haven’t started yet I felt ready to start something. Firs off I did 15 minutes on the stationary bike, no resistance, but it was hard enough and it was a start. Then during the week I got to the pool twice and swam for 10 to 15 mins. Again not very much but a start. and then just now I have done 20 minutes on the bike.
The annoying thing is neither form of exercise hurt my knee, so yes I could have been doing this for months but until now, now I am focusing on my mental health I have not been able to exercise, so clearly the 2 issues are very tightly linked.
My plan for the coming week is to swim each morning immediately after dropping my daughter at school on the way to work. Let see if I manage it.