I keep getting this icon. I don't know what it means or why it keeps showing up. This morning I had my phone charged while I was sleeping, so about 7-8 hrs, and it was on full battery. I used it for 20 minutes and it dropped down to 70% with the explanation point icon. I left my phone for a few minutes while I used the bathroom and it was drained to 60%. I restarted the phone and when it came back on, it was completely drained to 1%. And now it won't charge and it's been on 1% for a while. Please help. If it helps, I've been using the phone for 7 months.