Question about Skype use

[BBlack19]

I'm currently in Iraq right now and have the D2G. I got the unlimited global data plan just before it went away so I'm good there. I also have an account with skype and pay $14 a month for unlimited calling and all that good stuff. My question is, if I log into skype on my phone, will I be able to make phone calls from the phone using my skype number and not be charged anything? I had heard somewhere before that it will use your regular plan minutes and you'll still be charged the $2 something a minute. I'm not sure if this is true or not and I'm curious before I try using this. I appreciate any info anyone can give me.