Your mindset as the employee is, I'm bringing more value than my comp is worth. The employer mindset is, if I don't give this raise, will they walk and do I care. That's why sales guys have the top salaries - its easy to quantify - they bring in - make ALOT of $, or they don't and are out of a job. With Devs its harder, so you make your case.
Another thing, managers higher up who make the decisions don't necessarily know who is good and who isn't. Especially introvert devs who are the farthest thing from self-promoters. Your interactions with your boss, annual reviews, kudos, etc.. should give you some idea how well you are liked. Well liked people get raises because losing them hurts.
I wouldn't be too timid then - and ask directly. Not this "can we please discuss further". Rather, "I would like a 5% percent raise. Here is why I deserve it." Could be job accomplishments. Could be speaking, helping marketing, extra-curriculars.. Any chance to quantify with numbers is good. You'll get it, or not - or get part of it. It's just business and you are likely much more emotional about it then your employer, who deals with this thing all the time.