All anti inflammatory medications can have an effect on the lining of the stomach, esophagus, and other GI organs. Stopping the medications is usually the best way to prevent the symptoms. Some patients can take these medications for a long time with no effects, while others are not so lucky. Celebrex is purported to be the least irritating of the NSAIDS, but this certainly does not make it symptom free. If you plan to take these medications for a long period of time, be sure to contact your doctor if you experience any black tarry stols, bloody vomiting, or stomach pain. Many physicians will prescribe medications for the stomach to help protect it like Nexium, Pepcid, etc. If you are not taking the medications any longer, I would doubt that any gastro effects would be caused by previously taking them. However, once a person has had an ulcer or other major irritation caused by these medications, they are cautioned for life not to resume them.
Out of curiosity, what are you taking these medications for? There may be others which would provide grerater assistance to you with fewer side effects.