2yr girl complaining from tomy pain and pointing to belly bottom which shows a small pump comes outside can she wait to tomorow?

Tummy pain: Tummy pain around the belly button is very common in kids. If there is no fever, vomiting, diarrhea, difficulty breathing, she can probably wait. If the pain is severe, she cannot eat or drink, throws up or having runs - she needs to be seen.

Umblical Hernia?: If she is not vomiting, has no , diarrhea, pain is not very severe and constant and you are able to push the lump in with your hands, she can wait till tomorrow, otherwise take her to er. From what you are describing, she may have uimblical hernia and if it can be easily pushed in you can wait till tomorrow. But if the pain is constant and lump can not be pushed in, or she is vomiting, than take her to er.