don't base your bike fit on the stand over height, are you gonna stand over your bike or ride it? Stand over is more important on a mountain bike because the terrain isn't as predictable as riding on paved roads, if you have to bail from your saddle you want to have more room between the top tube and the jewels. Riding a road bike on the streets the only time that comes into play is when you stop at a light or you're getting off the bike so its hardly the basis for figuring out if your bike fits or not.
Fit is not as simple as "I'm 5' something so I ride a 50 something cm bike" there's too many variables but the most important is comfort. Does your bike give you back pain, wrist pain, neck pain, knee pain? All of these will let a fitter know what needs to be adjusted. It also depends on what bike you ride and your body dimensions, I can comfortably fit bikes from 54cm to 58cm depending on many adjustments so don't give up on what you have now until you have exhausted all adjustments possible.