If I got a 1099-R, J in Box 7 (J=Code "Early Distr of Roth IRA") why does it say I have to pay more taxes on it? I already paid the taxes when I put it in, right?

I had a large "Federal Due" and after entering my 1099-R it wiped almost all of that out. Why do I have to pay taxes again if I already paid it when I put the money away, that's the "Roth" part, right?  Also, I took it out because I was unemployed and needed it to live off of.