red-headed turtle?!

plz help i m so confused! ok 2 years ago i bought a really cool turtle from the pet store and brought it home. in 3 weeks it got out of its outdoor pen and got away. three days ago i found it on the front porch and i knew it must be him because he is so unusual. he has a sort of red head and the shell has rounded square sections on it with some yellowish design and some swirlies. if u guyz cant picture that then tell me and ill put in a picture. but plz help if i dont no wut he iz i dont no wut 2 feed him and then ill have2 realease him again and i hope u understand because i really like him. plz! if u guyz help i promuise i will be soo grateful and yall will feel good because youve done a good deed so plz!