I think a few chunks is a great way to experiment. It's becoming really popular right now to do color that way, even in very upscale and fairly conservative salons. I think purple tends to look good on almost anybody. You might get the "bug" and decide crazy hair dying is something you want to keep doing.
I know quite a few young, hip mothers with tattoos, piercings and crazy hair! Coloring your hair funky is nothing new and you are young. We all get "comments" from time to time, but I've found at least 50% they're benign or positive. My mother warns people about my hair, though, which I consider weird.
I was going through an adoption (we are still in process) and worried my hair & style might hold me back, but no one ever said anything about it. It was an international adoption, so I did plan to color my hair "normal" (or at least burgundy) for the trip to China, though.