4-(propan-2-yl)phenol im assuming that small peak is the OH?
That's what I think it is, and the small peak is the OH, in your actual spectrum it is under the aromatic signals.
If you did an exchange with D
2O the OH would become OD and the integration would change from 5 to 4.
Or you could expand the aromatic portion of the spectrum and then you would see it a bit clearer.