Running Short Sizing Help

I have 28" waist, 5’7 tall. I was browsing Eastbay for some running shorts, I’m not sure whether to get size small or medium… on the sizing charts it says size small is 30" waist, medium 33". but the compression shorts i have is medium size and it’s tight as hell and the regular running shorts does not have a size on it, i suspect it is small. I don’t want something that baggy , i just want a good fit, not loose, and not tight 4-5" instream, can someone help me out here?