First, congrats on getting your first gig. Thats the first step.
To answer your question, it is seriously up to you to prove yourself, show value, and become invaluable to your employer. Not to be harsh, but no one is entitled to give you a high salary. And, no one is going to until you 1) have experience, and 2) have proven that you have the skills that value more money. Remember you just started. You can’t expect top money at this point.
As far as what the norm is in the industry for an entry level designer? That varies depending on where you are and who you work for. A salary in the mid-west is going to be lower than a salary in NYC. But I can tell you that even that higher salary in NYC is still going to be hard to live on due to the cost of living. When I started I still picked up freelance gigs and worked as a cook in a restaurant to make extra money.
You will get there. Do you time, prove your value, pick up extra work, and if you feel you are not getting compensated like you should, look for a place that may give you that. Just know that right now you are not in the position to demand too high of a salary.
J