I went to the doctor but they were next to no help on this:

I am currently in my 3rd week recovering from a pulled lower back muscle - Couldn't walk for 2-3 days after pulling it during exercise (burpees).

It is still a little painful (acute pain) but I am mindful that the longer I leave it the weaker the muscles in the back will become.

Any advice on recovering from this and exercises to get me back on track.

I was thinking of doing a few bodyweight exercises to start with a bit of stretching (e.g. squats, press ups, pull ups etc..)

May go for some long walks as well.

I also work in an office so that doesn't really help.