@burcidi-- There aren't any other symptoms because leukoplakia is the name of the lesions itself.
Sometimes it may not look like a lesion, but a lump. Doctors differentiate between leukoplakia and other lesions by looking at the appearance- color, thickness and how long it has been there. Usually, it lasts much longer than a couple of days. Mine usually last close to two weeks, and return at intervals.
They're not painful, but sometimes it causes some discomfort while I'm eating. And I hate their appearance. Mine are either white or gray and feel different than the rest of my mouth.
You can check out leukoplakia pictures online and compare them to the lesions you get to see if they're similar.