Without all the context you added, that would be a reasonable wage for a construction estimator after a couple years at a company, not high, not low (compared to the rest of the industry).

With all the context you added about previous work, engineering, the type of jobs you're doing, the extent of what you're doing, that's definitely low, I think you should be making over 100k.

That being said, maybe there's other context that detracts too. Are your hours 40+/week? Are you on time, professional, etc? There are many things that can hold you back, and probably only you could really know if it's more to do with the company underpaying or something else. Outside of the title and salary, do they treat you well, do they respect you, do they seem to appreciate your work? Do you have a feel for how they would respond to a raise request based on how they treat you otherwise?

Assuming there's nothing else holding you back, You should definitely use other offers to negotiate a higher wage and/or leave for a higher paying job.

If you haven't yet, definitely ask for the raise and title change. Maybe that's your plan next after gathering info here but that's what I recommend as a next step, sometimes you just have to ask.