Had a meeting with about 5 people, 4 of which showed up, 1 of which did not.

Guess which one was the subject matter expert without whom we spent 55 minutes positing what-if's that could've been easily answered if that individual was there?

Yup. Never rescheduled, and that was the end of that conversation.

PM: You've heard of <thing> before right?

Me: I know the name of it

PM: Perfect, your the subject matter expert now.

Me: thanks...

"Oh, you only know 10% of how these algorithms work? You're now the subject matter expert, so you get to write the code"

Hello everyone, looking for some career advice here.

First of let me list my credentials off here. I graduated in 2016 with a BS in Computer Science. While I was working on my degree I worked as an engineering for 3 years in a cell phone repair company. What this entailed was managing/reverse engineering a software solution of one of that companies vendors, writing documentation etc (it started as a summer internship and became a job that I worked full time over Summers and up to 30/week in the school year).

Anyway, the vendor I acted as a point of contact offered me a job before I graduated and I started with them in May 2016 as a junior most Dev. Since then I have have maintained the same job tittle (software developer), however my duties have increased.

Currently I maintain several of our build servers, manage software releases (as in I am the lead developer of this application) for the service that makes 90% of this companies money, and am the subject matter expert for everything regarding smartphone diagnostics. I've literally been entrusted with access to all of the company servers for if something goes wrong. I'm also training our newest developers and being told I'm doing a good job at doing so.

Currently with my job on a day to day basis I'm working with Java, Android, C++, Golang, MongoDB, iOS in Objective C, and Python

(Please note this is a small company of less than 50 people)

Currently I'm only being paid 60k USD and am wondering if I should hold out for a raise or consider looking for a better job? ( Please note I live in the east coast in an area where the cost of living isn't absurd).
Because this job was practically handed to me I don't know what to expect and feel imposter syndrome as I think I deserve better pay but think I don't have enough years experience. All advice is welcome