Girl who is a friend looks down, smiles and blushes?

We've been friends for about 18 months and have both been flirty and sometimes tactile but nothing serious.

I was asked about plans for the following evening when a few of us were going out to eat and i put my hand on her shoulder and said she was always welcome to come and she looked down with a big smile on her face and was blushing.

the thing is, only a few minutes before she was hugging a couple of guys who she hadn't seen since around Christmas and was fine with them, and when i've seen her lately she's always hugged me so it kind of surprised me that she'd be a bit bashful now. It's not the first time i've had my arm on her either, although the last time was when we were out and kept bumping into each other when we were walking along the street having a conversation.

I didn't plan on embarassing her but did wonder if it could be anything else especially as this is the first time i've ever seen her blush around me.
She did later say she was shy which i didn't realise and some of her body language during the day was different as well.

Whatever it was i'll be mindful of not repeating it anyway as i don't want to do anything which might offend her from me not thinking ahead.

Girl who is a friend looks down, smiles and blushes?
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