New MacBook Pro: 13" or 15"

Hi everyone,

I'm moving from my old computer based on windows to a Mac. Next year I'll attend the university, so I'm not thinking of buying the iMac. I have to decide between the 2 models of MacBook Pro with retina display( since the difference between the air and the 13" pro retina is just 100$). My budget is about 2000$ so I could buy the 15" base model. My question is if it is worth to buy. I use a lot the office suite, photo/video editing ( but not to much), surfing the web, watching movies, and other ordinary things, and I think next year i will be using it more time and I'll be doing more thing. Moreover I can't change computer each 2-3 years, so what I'll but should last at least 4-5 years ( am I crazy ? :-D ). I'm wondering if the 13" retina is enough powerful to let me do all that I need without problems, or if I have to move to 15".