Don't stress... it is probably not your spleen
Your spleen helps your body resist infection. If your spleen has to be taken out, you are more at risk of getting severe infections. Your risk of infection is highest in the first 2 years after you have a splenectomy. Your risk will also depend in part on your age and whether you have other diseases. Since you are young and healthy if your spleen needed to be removed you should be OK.
First of all there is a good chance this has nothing to do with your spleen what-so-ever. You could have pulled/ strained an abdominal muscle. You could have a hernia. Please, do not get all worried. The important thing is that you get checked out thoroughly by your doctor. Pain is your body's way of telling you something could be wrong. I have a good feeling that your spleen is not the issue and that is probably something minor. Just go see your doctor and be honest with him. No matter how embarrassing or trivial something may seem, talk to your doctor honestly and openly.
Let us know how you are. Take care.
Cheers mate :wink: