Is it common for a published paper to have some small mistakes? I submitted a paper for publication several days ago. This was a resubmission after I had responded to the critique from the reviewers for my first draft. However, while I was looking at my data again, I saw that there was a section where my data points increased between phases, but I had written that they decreased. What's more, I had qualified why it made sense for the values to decrease, according to literature, so it's possible that the data I acquired was flawed. The reviewers had not marked this, and I had missed it upon reading through everything.
Apart from this, there is a missing comma and a missing word at another spot in the paper.
What I'm wondering is, is this a common occurence? And would it harm my credibility as an author/chances of getting published?
I can tell you with absolute certainty that almost every published paper contains at least one minor mistake. At the very least, I know that every single one of my papers has at least one typo that survived several rounds of reviews and revisions, and I can always find an error or two in every paper that I read carefully.
If the error is not a substantial one, i.e. one that significantly impacts the validity of the main results, then you shouldn't worry about it too much.
If you realize that your methodology is broken, your data is wrong, your theoretical analysis has logical flaws, your conclusions contradict known results or something of the sort, then it is worth considering taking some immediate action. The ethical thing to do would be to contact the journal's editor before the paper is published and have it retracted (as painful as that may be), and resubmit it if/when you manage to fix the problem.
For fixable mistakes found after the fact, some journals publish errata - appendices to the published paper that resolve issues found post publication.
If it's just a typo (missing comma/missing word/use of antonym) then don't stress too much. If you feel like the decrease/increase typo is in a key sentence describing your results (say, the intro/abstract, or in the sentence describing the key findings), it may be worthwhile to contact the editor and ask to resubmit a correction.