I'm really confused. i'm 5'7-5'8ish and 140lbs, I always wear a 25/26 in pants so an XS/2. yesterday I was online shopping at a website I've never ordered from before and did the suggested size calculator because I was unsure which size to order because of the brand, and it told me I was a size 8 based on the physical info I gave! now I'm here wondering if I've been wearing the wrong size the entire time?? I fit just fine into XS/2s so is this abnormal??