You should never hesitate to consult your Stomal Therapy Nurse as soon as you experience skin problems or complications. However, spotting evidence of leakage early can help you to catch a potential skin problem even before it develops.
Start by looking for stoma output, either on your skin or on the back of the adhesive baseplate. Even if there is no direct visual sign of leakage, be aware of anything unusual, such as if the adhesive baseplate looks 'melted' (because the adhesive has reacted with the output).

Signs of mechanical irritation
If your skin is red, sore and moist, maybe even bleeding a little, but you have not had any leakage, the issue could be 'mechanical'. That means your skin is simply being irritated from removing the pouch too often, too vigorously, or from cleaning or scrubbing the skin to roughly.
To avoid mechanical irritation, try to be as gentle as possible, both when removing your adhesive plate and when cleaning the skin. Try to peel the plate off slowly, rather than ripping or tearing it off. Using the other hand to hold the skin tight can help reduce stress on the skin.