lactose intolerance

Whar exactly are the signs and symptoms??? My whole life milk has made me 'sick to my stomach' but ever since LO was born, every time ive had a glass of milk, ive gotten indigestion so bad that i legit felt like i was dying...this really sucks because i love milk   but im afraid to drnk it now.

My eldest and BD is lactose (I think my youngest is too but it's to soon to tell). As soon as my eldest drinks something with milk as an ingrident or cheese he gets the smurfs almost instantly (within 10 mins) my BD lasts a little longer but he gets an upset stomach as well and feels like he's gonna puke.