How to know for sure
A peristomal hernia usually appears, because the ostomy surgery creates a weakness in the abdominal wall, allowing the bowel to push forward. If you can feel a lump or a bulge around your ostomy it is a sign that you have developed a hernia. The hernia can vary in shape and size - from a golf ball to a grapefruit or larger. It can sometimes be visible through your clothing.
If you suspect you may have developed a hernia you should contact your ostomy care nurse to get the area properly assessed. In some cases this will include a scan to confirm the diagnosis.
I have a hernia - what now?
First of all: you should not be worried. Hernias are a very common issue around people with an ostomy and it is very rare that hernias cause major issues. It is, however, not unlikely that you will feel some discomfort at the end of the day when your muscles get tired.
You should also be aware that because the shape of your ostomy changes due the hernia, your ostomy solution will probably not fit as well as previously. This can cause issues such as sore skin, leakage and other complications.
Your ostomy care nurse can help you make a reassessment of your ostomy solution to help you resolve issues, before they occur.

Will I need more surgery?
Major complications are rare with a peristomal hernia and in most cases you will not need further surgery. In fact, making key life-style changes such as exercising more regularly or following a more balanced diet will have a more significant and long-lasting effect than surgery.
Of course, if you experience symptoms such as severe pain, feel sick - and more seriously - if your ostomy changes colour or stops working, you should immediately seek medical advice from your general physician.
What you can do - and why it matters
There are several actions, big and small, you can take to reduce the impact that hernia has on your life. As mentioned earlier it is not uncommon to experience a dragging feeling at the end of the day, when you abdominal muscles get tired. This can be helped to a large extend by strengthening your core muscles.
Weight management is also a good place to make an effort, as being overweight can cause undue pressure and strain around your ostomy.