How did you afford it? I had to work my way through college and needed a paying job the minute I graduated. There's no way I could take an unpaid internship, which by the way is pretty common in the ad industry (and disgusting, IMO, as summer interns are treated like gofers).
I lived on friends' sofas (I paid them back later) and then for free in a building which was scheduled for demolition. I did every bit of assisting for cash which was offered and also worked at the weekends. The agency paid my travel pass and quite often someone there would feed me. I lived from day to day on very little money without ever really planning ahead - which is exactly how it should be when you are in your early 20s.
Speaking about the free internships.. I didn't ever do it but I wish I had. When starting out - out of high school I thought that University was very important (and it probably is important.. at least a bit). I did a degree in photography and ended up with very little that I could actually apply to running a studio or making a living any other way as a photographer. At the time I also visited a photo studio that offered to take me on as an unpaid assistant but I didn't take it because I felt it was a rip-off.
In retrospect, if I wanted the best education to be a professional working photographer I should have worked for free for 4 years for the photographer and save the uni tuition and I would have been a lot further ahead than 4 years of university. I learned lots at the uni as well but not much directly related to working as a photographer.