I am a 9 to 5 person and I usually take walks of about 3.5km and I usually get back about upto 45mins before I am in bed, am I doing any harm or good, tend to do this everyday...
fair play to you for having the energy to head for a walk after work, it can sometimes be daunting. Physically no, you're not doing any harm, this is a good work out for everyday, it probably helps you sleep at night. If you are walking at night though just be cautious of traffic on roads and your personal safety! otherwise keep it up!