Hello Tina, I just now tested your publishing and didn't have any issues with it. You had 17 credits prior to publishing and when the image was published you had 7 credits left (I reimbursed spent credits to your account).
Is it possible that your page shows the cached version of credits? Meaning you actually have fewer credits then shown?
Can you please try to clear your browser cache before publishing the image to see how many credits you actually have?
Also, do you get information that you don't have enough credits when you try to publish image?