Can you get IBS at any age?

I am 18, healthy weight e.t.c. and never had any allergies or trouble eating any food in my life, even including extremely hot curries for example. I've always had a strong stomach for anything i ate. However the past couple of weeks i've began getting diarrhoea after eating some meals (both cold lunch things, and warm dinners upset it) And gas/cramps from a lot of foods too. There doesn't seem any link between the foods i eat to cause it, in the last 2 days both curry (for dinner) and ham and crackers (today's lunch) caused it. While the day before this i ate pie and chips which caused no problems at all! My nan suggested IBS so i just wanted to find out more, and whether this sounds like it? Thank you xx