Rolling over

My daughter just turned 3 months old and she keeps rocking side to side when she’s laying on her back. She looks like she’s going to start rolling over soon. At night we don’t swaddle her. She never liked it. She would actually scream when we tried to. So we just put her in warm zip up pajamas. My question is, is it ok if she rolls over and lays on her belly to sleep this early? Since we don’t swaddle her, I know she’s going to eventually do it. I just want to make sure it’s safe