how do I tell if baby is teething?

Jackie • 24 y/o Jake G 💍 mama to LNG 4/21/17 👶💙. SAHM . Idgaf about your opinion. It doesn't phase me🙌I say whats on my mind. Gtfo my page if your a hater. I don't need that type of drama. Stay blessed . 🙏🏻
My baby will be 2 months on Wednesday. He has been very irritable lately, he always wants to chew on something like my fingers or his pacifier. I've noticed he had little white teeth that aren't out yet but they are sticking out the top part of his mouth on his gums also he's drooling a lot too. How do I tell if my baby is teething?