I was put back

[lukre]

What is the meaning of this phrasal verb in this context? I couldn't find the meaning on the internet.

Here is the context:
"When you look into somebody's eyes, you can usually tell what their eyes are saying. I was not getting any kind of read from her at all, so I was kind of put back, which is not usual for me in that I felt
uncomfortable with her staring at me the way she was."

Thanks a lot!

[billmcd]

Taken by surprise, "off (my) guard" or an unexpected reaction/emotion.