Saturday morning charge

I did not charge my 16gb iPhone 5 in black at all on Friday but I did charge the phone twice on Thursday.My cell phone battery was really low and at 32 percent.My charger cable is pink and I bought the charger last Christmas at Walgreens drug store.I check to see how much it has charged once in awhile.I think the battery in my iPhone drains pretty quick.My parents gave me the iPhone for my birthday 2 and a half years ago and have just finished paying off the phone on their cell phone bill.I would love to get an iPhone with more gigs in 2018 such as 64 gigs and get the iPhone 6.