How can I prevent my stomach from making wierd noises and possibly gas?

Is it the milk perhaps? My mother is lactose and tolerant but on the other hand my father isn't and as a child I grew up eating a lot of cereal for breakfast and whatnot and never had any problems until about a year and a half ago in 10th grade. For instance, I'll be in class, and when I'm taking a test or when it's very quiet, sometimes my stomach makes weird noises and I'll feel like I have to pass gas lol but it's a lose-lose situation because if I hold it in sometimes it makes a loud, weird noise almost like a hunger growl but a little different and it's embarrassing so either people hear it or I try to cover it up by ruffling up my backpack or clearing my throat lol. I'm not really sure though if it's the milk that may be causing this though, at least not all the time because I've eaten cereal plenty of times in this last year and a half and I've been fine throughout the day. But like I said, some days it happens. For the love of God is there any way to prevent these noises? I'd greatly appreciate feedback. Thank you. By the way, I've heard chewing gum can cause this sometimes and maybe that could be part of the reason too because I chew gum basically throughout the entire school day. What also does make sense is I heard sipping water throughout the day can help cure this and at lunch everyday I drink water so I don't know what's going on.