I am 24 and living a normal healthy life. My only worry is my behaviour in my daily life activities that are questionable which is to do with not trusting myself or my immediate past actions. For instance after locking a door I would bang the door 3-5 times to check whether I have locked it or not. Also, at night after switching off the passage light I would feel guilt that the light is still on and needs to switch off so I would wake up and check/verify whether it is on or off.

Is this normal behaviour?

Thanks

I would suggest it's at the edge of obsessive compulsive disorder, but (although I'm no expert), it doesn't sound completely abnormal.

OCD behavior becomes a problem when it affects your daily life - e.g. you recheck the door 20,30,40 times and you get up multiple times to check the passage light.

Obsessive-Compulsive Disorder (OCD): Symptoms, Behavior, and Treatment

This is a good site and provides some great strategies for dealing with it plus some links to other sites. I hope it helps!