Here's the thing. This fibrocystic breast is exactly what you would expect around such an age. Whether there's actually anything dangerous going on is impossible to tell because in the worst case there could be another problem behind that outer tissue that goes unnoticed.
The real problem is your body itself. You're at a stage of moderately fast physical development and while the process tends to often misread building codes, there's no reason for you to be alarmed by this. Even if there's some sort of abnormality, you're simply not familiar with your body while it's developing. I don't care if you examine yourself every day, there's just too much going on internally.
With that, routine examinations should not be done at your age. Addressing every single abnormality that arises is tedious work and you're not at any significant level of risk for things such as breast cancer until you're around 25. I think the ACS says 50 but the way people's lifestyles and health have changed in recent years has me suspicious of this and I'm not going to agree with the record. In terms of personal value, it's probably best that you do get whatever it is examined. You're not going to die from noticing a small lump but at least find out if it's a potential problem.
I notice tiny lumps in that area of my body every few weeks but they're usually just clogged pores caused by bad/dirty fabrics and sleeping in said clothes. Unless you share this stupid behavior, that's probably not going to be an issue. What you describe is likely much bigger than random body acne but I figure it's worth mentioning. Just pay attention to what's going onto and into your body. It's good to be aware of potential problems and managing them before they become serious. That's called maturing. :/