iPhone SE not turning on after losing battery

My phone has been having some battery issues lately, losing battery fairly quickly and self-restarting often. It ran out of battery after a restart, and I've had it plugged in using various outlets, cables, and computers for about 5 hours now. It recognizes that it's being charged (it shows the charging screen) and when it's not plugged it (it shows the low battery screen and tells me to plug it in), but it just won't turn on. I also can't access any data on it using my computer. Do I have to get my battery replaced, or is there something else I can do?