How much Pediacare (Acetaminophen) should i give my 2 month old baby to combat fever/pain?

He just had his 2mth old vaccinations, and while the doctor said we can give him some if fever develops she didn't say how much. i hadn't noticed that the bottle's directions say infants under 24 pounds or under 2 years of age ask doctor. again, doc said we can give him some but not how much. the dropper it comes with is 0.8ml max, with another line at 0.4ml. The recommended dose for infants or children 24-35 pounds, is 1.6 ml. My baby is 2 mths old and weighs just under 14 lbs.