Visit a nearby dentist firstly. He will check the mobility,tenderness,discolouration,even dislocation if any.

Get the intraoral x ray done,u may need to undergo Root Canal procedure.

its important t take an x-ray...is d tooth moving...

You should have visited a dentist on that day itself. Nonetheless you should not delay your visit any further and plan for an appointment as soon as possible so that the exact condition of the teeth and gums and the bone can be evaluated and the treatment plan can be delineated for you. Modern dentistry itself relies on the fact that we will make every effort to save a tooth and extraction is kept as the last option, especially at your age. But if the patient does not visit the dentist in time there can be Irreversible damage leaving extraction as the only option available. Regards.