Is it extra skin or still fat?

I think it may be extra skin because I lost 55 pounds from 235 to 180..and I weight lift and run 5 miles a day so I thinkt hat I shouldnt have any more fat on my body...I think it may not be because I am only 20 yrs old, so I am young, and ppl have lost more weight than me and haven't had left over skin...But...I am skinny everywhere except on my midsection, especially below my belly on, and a little fat on my chest...should I get a consultation for lipo or a tummy tuck?