I have developed a tiny slit at the top of my tongue, i also have my tongue pierced, is this the problem? what will i do about it?

Anemia or vitamin deficiency is reportedly a cause of increased lacerations or small cuts on the tongue.

If this is true, then a small tweak to your diet should sort the problem out.

However, if the cause is anemia then you'd be displaying other symptoms on top of the splits in your tongue.

I can't see how your tongue piercing is related though, unless it's positioned anywhere near the injured area.