My objective opinion is that it's your body, and as long as you are taking precautions and preventative measures like using protection, knowing who you're sleeping with, and getting tested once a year or so, then that's your prerogative. You are however under the legal age (maybe not where you live? idk), so you are not only very young psychologically/emotionally, but sleeping with people over the legal age can mean problems for both of you. It's also peak years for adolescent angst, which can contribute to impulsive or rebellious acts like this that you may not otherwise do.
My personal opinion is that, yes, it's a high number for someone your age. 17 is very young. You may be nearing physical maturity, but mentally, it's a very different story, no matter how "mature" one thinks they are at that age. At 17, most are not ready to be parents or reap the consequences of pregnancy. I don't agree with slut-shaming but I do know that word spreads and people will and do talk. And unfortunately, girls still get a lot more flack for promiscuity than guys do. My closest friend from childhood became "that girl" in school. She was the popular girl all guys wanted, but once they had, didn't anymore. She'd try to hook up with people at parties but people refused her as they'd "already been there, done that." She ended up having a kid at 19 and straightened out, but I still remember how people talked about her behind her back or used her. She also had the "free with her body" approach, but anyone close to her could tell she was craving something that simple hook-ups couldn't give her. But perhaps your situation is different. Whatever the case, be careful with who you sleep with and always use protection no matter how heated things are. Some honest introspection can't hurt either if you do suspect there's a deeper reason to your motivations.