Hi mama! Five months is still a bit early for actual teething, most babies start showing signs around 6 months, though some can be earlier or later pa. The drooling and chewing you're probably seeing now ay normal sa stage na yan, kaya hindi pa necessarily sign ng erupting teeth. A few of my mum friends have babies na nag-start ng teething signs around 5-6 months but the teeth didn't come out pa until 7-8 months, so it's really case-to-case! Best to just monitor kung ano talaga ang signs, swelling ng gums, fever, or persistent biting, and ask your pedia during the next checkup para ma-confirm niya if it's actual teething or just the normal drooling phase.