You're 14 and he's 16 ummmm aye just make it work, screw your step-mom she trying to but into your ****. I'm not from America, but I know that as long as nobody can really tell the age difference and as long as your step-mom doesn't call the police (whatever the laws are for your country/state) then everything is alright keep being with him lol. Just hope for yourself that you two will still be fond of each other, if he is going to college you better hope you keep talking and stuff, otherwise someone else will come ^^. I look at it like this, if two people were already dating and both were under the age of consent or whatever it shouldn't fooking matter, then all of a sudden one of them turns "that" age, it still shouldn't fooking matter. As long as the relationship is good and he/she is a good person everything is alright. You can respect your step-mom for worrying, but don't let her fook up your shite OP.
Technically the law is that someone over the age of 18 can't copulate with a minor, something she probably assumes y'all are doing. But to get even more technical there is another law that coincides with that one called the romeo juliet law that allows the two to do so provided the age difference is no greater than 3 years
In two years you will be 16. That is the age of consent in many jurisdictions, and if it isn't, there is often a "Romeo and Juliet" clause in the consent law that allows for one partner to be underage provided the age gap isn't too big.