There have been cases where people were infected by getting a tatoo, piercings, or even a manicure, when the place of business didn't sterilize their equipment properly. That said, I agree w/what was said above.
The treatments these days are not the huge inconvenience they once were, and they're a lot more effective. You'll be on the sideline for a brief time, but you'll be ok.
I do agree with the others, that it doesn't matter how you got it, just focus on subject,and find a food hepatologist/infectoligist, with experience in treating people with hep c! Good luck,you are still young don't vorry, you just need to undergo treatment depending on a genotype,and liver stage fibrosis.all that will good Doc.tell you!
I know it's probably frustrating not to know exactly when you were infected but in the bigger picture of things it really doesn't matter that much. You said that you used at least 3 times to 5 or whatever so it was likely one of those times. What matters is that you find out how much damage HepC has caused for you and when you will need to get tx started. One thing on your side is that you're young and it's a slow moving virus, so you may have some time to wait until you need to tx. That said, you gotta find out where you stand, so find a good hepatologist doctor and get a liver biopsy, ultra sound, or whatever and take it from there. good luck
Some people never know how they got hcv, but it only takes one contaminated injection to get infected though. The important thing now is to get treatment, and not dwell on how you got it.