i work in Virginia and After taking a lunch break i came back to work a little late from it like 7 minutes. My boss asked me where i was and I explained that i had to run an errand and took me longer than I thought she then continued to yell at me in front of a co-worker and adminstrative in another department. And told me that i had to deduct 15 minutes off my pay check becuse "as soon as it hits after 2:30 it's considered 2:45" Is this right? i was under the empression that you weren't allowed to yelled at employees in front of other employees? And is she able to deduct 15 minutes from my pay for that?

There is absolutely nothing whatsoever in the law that says you can't be yelled at in front of other employees. It may or may not be good management, depending on the situation, but it is not even remotely close to illegal.

Whether you can be docked the 15 minutes depends on their overall rounding procedures. It is legal to round an employees time in up to 15 minute intervals as long as it is not always done in the employer's favor.