Very active and then sudden sleep...

[Plasma]

Hello everyone! This is my first post here and I am very concerned with what had just happend with my Syrian hamster, Sandy. I got her yesterday and got her in my hands for the first time. Everything went well, she seemed to be active and comfurtable with me for about 15-20 minutes until I put her back in her cage. She wondered to her wheel where to ran for a couple of seconds until she stopped, stared at something and suddenly got a fright. She got out of her wheel and started making like a purring groan noise and then stood still and started rolling a little onto her side until it looked like she fell asleep.

She is now very much active again and is running on her wheel like there is no tomorrow! I'm only concerned because I have heard that it may be instinct for a hamster to 'play dead' if they get a big fright and can potentially give them a heart attack but she looks very much fine now.