What are the signs of having thrush?

Varies. Initially, you may not even notice symptoms of oral thrush. Once it progresses the sigs can include: creamy white lesions on your tongue, inner cheeks and sometimes on the roof of your mouth, gums and tonsils, lesions with a cottage cheese-like appearance, pain, slight bleeding if the lesions are rubbed or scraped, cracking and redness at the corners of your mouth (especially in denture wearers).
Irritation. Usually associated with a white coating of the mucous membranes. In the mouth it can be associated with pain/irrition, redness of tissue, difficulty eating or swallowing. In the vagina, it can be associated with itching, burning, dryness, white cottage cheese like discharge.