Please help if a doctor says something about your spleen having a chance to enlarge or having mono and says to come back in a week could it to late like ding or something before then

Big Spleen. Mono can cause enlargement of the spleen but it is also the job of the physician to educate and warn patients about possible side effects of illness. The doctor is simply wanting to make sure you are doing well in 1 week.
When . When a person has mono the spleen tends to enlarge. For this reason doctors tell their patients to take it easy and not play sports because there is a chance the spleen could rupture; this typically happens if you sustain a hard blow to the abdomen or fall. Once the mono resolves the spleen starts to go back to it's regular size. You should be fine as long as you take it easy. If you develop abdominal pain, nausea, or vomiting seek medical attention right away. Good luck.