Ever since I was as young as a few months old I would lay in my crib on my stomach or in the fetal postion except facing down, put my hands on top of eachother in front of me and hit or "bonk" my head on my hands.

My parents got worried and asked the doctor but he said it was a form of relaxation and it wouldn't hurt me in any way. But I've been doing it for 15 years now. When I was younger, I was almost every night but now its about a couple times a month. I also do it when I feel sick. In the car ill do it by hitting my head against the back of the seat. Sometimes I hit it really hard, hard enough to bruise my hand and head. I also will wake up to myself doing it and not even knowing it. And when I do it for a long time its as if I fall asleep while doing It.

So I dont know but is this affecting me at all?

I would recommend creating a new habit that will replace your old habit. A habit that will be healthy rather than cause possible injury. A possible solution maybe to utilize a facial massage and use a similar rthym as you do when you are hitting your head, without the impact. Whatever you choose to do... focus on loving thoughts during the process...in time this may give you the same comforting feeling.

Head banging is a common rhythmic habit among children, like thumb sucking. Some theories explained this behavior as a habit that  provides pleasure related to movement, the kinaesthetic drive.

For some children, head banging is a way to release tension and prepare for sleep. Some kids bang their heads out of frustration or anger. It is an effective attention-seeking maneuver. The more reaction children get from parents or other adults, the more likely they are to continue this habit. For most children it occurs at sleepy times or when upset. This behavior can last for minutes at a time -- or sometimes for hours. It can even continue once the child has fallen asleep.

This behavior is abnormal, though, if it persists beyond the early years. Normal head banging usually goes away by age four. Most children will outgrow the habit on their own. You can speed up this process by reacting to it in a matter-of-fact way. Older children who bang their heads may need the attention of a psychologist. A psychologist can help the child find the source of their stress and teach them ways to cope.

However, if the habit persisted up to adulthood, the more troublesome the habit becomes. It can interfere with social life. It also disturbs sleep rather than help the victim to sleep. Sometimes the movements are violent enough to move the bed or jar the sleeper awake. This may happen every time the sleeper starts to fall asleep. He can have sleep deprivation.

No matter the age, if the rhythmic movements seem to be heading toward self injury, it's time to seek help. Things like hitting the body hard enough to cause bruising are symptoms that indicate the problem is getting way out of hand. Stress, anger and worry seem to make the disorder worse.

These things could help you to cope up stress. Exercise regularly, relax, sleep well, laugh more often, make time for fun or explore a hobby, improve your diet, find someone who will listen to you when you’re going through stressful times and positive thinking.