That sounds grim, there will be layers of stitches in the muscles I would’ve thought, not just one set, but I don’t know for sure…hopefully others who have had intra-oral surgery will reply, we have fewer members going this route of surgery now… @Deb7 is only a couple of days in front of you, maybe you could send a message & ask?
Here’s a link to a discussion by @Kiriez back in September
& one by @michelle with info, but I can’t see any mentions of when the stitches would normally come out I’m afraid…
Again, you could try messaging them? Praying that you get this sorted , that it does heal up quickly, & sending you a hug 
