Obviously we don't have the full details here but from what you have provided I wouldn't be fully convinced just yet she feels the same. It could be she is just being friendly and sees you as a good friend who she can confide in. You on the other hand seem to be falling in love with her!
Be very very careful or you could end up in a very awkyard situation with someone you have to work with on a daily basis. If it's not obvious enough that she's into you then she's probably isn't!
You need to sus her out more first. Check for signals of interest, dilated pupils etc. Does she flirt with you? Have someone else in the office find out (I know this is a little childish but it's bloody effective) and you need to know ASAP as you seem to be falling for her pretty bad
Also there is one other major thing you're forgetting. SHE HAS A BOYFRIEND!.........how do you intend to overcome this?
Originally Posted by
Perfguy 
The other day, we were in the back room together working on something and my heart started pounding so fast I grabbed my chest and had to take some deep breaths. of course, she asked what was wrong and I had to respond with "nothing".
This was your perfect chance to say. I'm falling in love with you and my heart is pounding, jokingly, and see her reaction