Social Security and Medicare wages (boxes 3 and 5) are less than my wages - Why?

So from a job I worked at a university as a graduate student, my boxes show the following:

Box 1 ~14000
Box 3 ~5300
Box 5 ~5300

I was a little confused by this and definitely got more confused when my wife's boxes 3 and 5 were higher than her box 1.

I looked it up and found that boxes 3 and 5 are typically more than box 1 unless you have an income of $118k, which we are far from making combined.

Any idea why this would be the case?