My phone (lumia625) ran empty on battery while on travel.... I charged it up to about 10% and took it for my walking exercise, it got empty once more..... I went to charge and the phone would alternately flash the battery charging screen and the nokia flash screen....turn off and battery charging screen and then the nokia flash screen. It went on like that for about thirty minutes or so....until finally the phone turned on. What i notice now though is that the phone is very slow to charge. Although the discharge rate is still seemingly similar to how it was before. My only problem is the charging time...which is so sloow now after the incident I described. Could i have damaged the battery?