Oh yes! I've had to do the same thing a lot, too :oops:
Don't worry, I think you'll do fine. Maybe you can use a different colour for the seamimg thread? So that you can see where your seam is more clearly? Here in this page there is a seaming method called Mattress Stitch used for side seam. I don't know if this will be helpful :shrug: But the result looks really great, and it doesn't matter if your seaming thread is in a different colour because it won't show.
So... I hope this is helpful! :hug: