Discharge or incontinence?

Usually right before I take a shower, I'll notice a small damp patch in the crotch of my underwear when I remove them and I can't tell whether it's like a clear discharge or a slight incontinence. It has kind of a strong smell to it and I think it's got a completely liquid consistency (like water, not sticky/stringy or anything). Is there anything I could do to tell which it is?