My phone wont charge

i recently discovered that my phone will not charge after i had returned from a friends house and the battery had died so i put the phone on the charger but all that happened was a small red light flashed once above the screen and nothing else happened. this happened every time i placed the charger in the phone. i have already tried using other chargers and that didnt work so i tried cleaning out the charging port and that also didnt make any difference. any help is much appreciated.