I see you're new here, so I'll just help you with your question:

via the SteamGifts guidelines (https://www.steamgifts.com/about/guidelines):

"Allow the giveaway creator one week to send the gift. Please be patient and do not contact them during this time. If the gift is not received after one week, you may contact the giveaway creator on Steam to follow-up."

Also, it's usually considerate to say thank you, especially for your first comment.

Welcome to SteamGifts, and consider yourself very lucky you won a giveaway so quickly after registering. I wish you all the best of luck in ongoing events.

I also just saw you are from Ukraine. Hope things are going well for you over there.