Ringtones for Phones

Ok I am 14 and I love to text my boyfriend and my two best friends. I have a prepaid phone with page plus cellular and it costs 10cents a minute I am not sure how much it costs to text but I sent about 50 text messages today and I ran out of minutes (I bought a 10$ card this morning) and my mom is really mad about it. I have tried not textig my friends but they think I am ignoring them (I have told them already that i can’t waste my minutes) and I mostly use them on my boyfried on weekends when I don’t get to see him. I am planning on saving my money and buying a better phone with cheaper texting (but I can’t get contract) I kind of want this one tellme is it a good deal http://www.wireless.att.com/cell-phone-service/cell-phone-details/?device=Sony+Ericsson+Z310a+-+Jet+Black+(Refurb)+-+GoPhone%C2%AE+(Pick+Your+Plan)&q_sku=sku1140057

I am not sure but I like that and their is a plan where you pay a dollar a day for unlimited texting which would probably be good for me.