The credits of a semester in a university are basically between 20 and 30, generally not more than 30 credits and not less than 20 credits, so 23 or 25 credits in a university belong to the middle level.

Generally speaking, if you pass a course with less than 30 credits per academic year, you must repeat the grade. However, there will be summer refresher courses, and there will be refresher exams and make-up exams soon after the start of school. If you can pass the exam, you don't have to repeat the grade.