I'm 5'4" and have dated men who ranged from like 5'6" to 6'4".
Some people put great emphasis on height (and our culture teaches us to do this). However, height is a determiner of genetics and nothing else.
I think if you're into this woman, you should value what she brings to the table more than you worry about your ego. I think it's very likely that any little twinges you might have about it would amount to nothing as you got to know and appreciate her as a person. (And, the same on her side as well).