HCG question

T • Mama to a miracle🌈 6/8/21

I had my beta HCG done Monday (3w5d) and it was a 17, today (4w) it’s 51. I know they’re supposed to double but I’m still worried for some reason. My period isn’t due til Friday, I’m super early but I just wanted to make sure this is an okay number?? Thx ❤️