I'm working as a developer for a company for almost 2 years. I have been an intern for 1 full year, and then got an official offer from them. It was a full time development offer but with lead responsibilities, to lead a small team and the main product of the company.
I did the mistake of accepting the offer straight away without negotiating, and now it has been 3 months with this position. I've realized that the work I'm doing is much more worth than what I'm getting paid, so I feel very bad in my current position. I basically feel that I'm being underpaid, and my coworkers have the impression that I get paid much more due to the amount of work I do.
I want to get paid more but I can't lower my current level and workload because that would be unprofessional. I like my current position but if I continue like this I won't be happy for longer and my motivation will decrease. I would be able to also look for a different job, but I think this position is a good opportunity since I have freedom and a team I can get along with. I've mentioned to my boss about having a performance review, but date has not been decided until now and I feel like I should push for it. For context, it's a growing startup in a big city in Europe.
Taking the above into account, how can I renegotiate my current contract to a better pay that is according to my position? Is it too late for me right now to consider this option?
Is it a good option to be honest in a meeting with my boss and just say "I feel underpaid"?