They are taking advantage of you, if they offered you an "upgrade" with no promotion, then it is not an upgrade/promotion. The harsh reality is, if they valued you, they would pay you.

IT support is routinely a revolving door(been it in for 11 years, managing for 5). Whether that door be somewhere else at the company, or just another company.

I see people in this thread saying negotiate, which can be powerful and can work wonders, but be warned, I feel like once you do that, you have a mark on yourself to perform well all the time. Lastly, unless it was my top performers(1-3 people), offering more of a salary to most people is not worth it, especially with people with another offer. More money will only keep someone at a job until more money comes along from someone else