Money invested in the pot isn't yours anymore, it should not affect your decision. When people say they are pot comitted, what they should mean (because they usually mean what you said) is that the amount they have left, compared to what they are poised to win if they have the best hand, is too great to even fold trashy hands.
You have 100 left and there is 3500 in the pot. Board is K8754 all heart and you are holding the Q of hearts. You are layed down 1:35 odds
on you calling, wich means that you need to be right 1 out of 35 times for it to be profitable. You will be right more often than that (you have the third nuts), thus you should call no matter what.
In this hand, you're not comitted and I don't like the play on the flop and turn and here is why.
You say that you bet a lot of hands are agressive but you choose the worst spot ever to be agressive: on the river. What hand can your opponents possibly put you on and reasonably fold: none. This means that you have no FE (or almost none) and are choping 100% of the time, unless you get reraised and in this case, you should fold 100% of the time.
Why not bet the flop ? At this point you have a gutshot and passive players have called you, wich means that a 5-9-9 flop are in their range, but all of them have checked. Also, why not bet the turn, since now, you can rep a 5 or 9. You have to understand that all boards are made boards, this one is just stronger, but it still can be beaten by a wide variety of hands (66 and up + quads 9). 9999A is a made board wich cannot be trumped, this is is not and you should be careful trying to rep. things on the river while showing no strength on previous streets, one time you will get burned and you are effectively paying 100 more to chop the blinds (or have a larger share of the blinds).
So, no, I don't think you played it right, I might call since it is sure that nobody has been slowplaying, but raising opens the door to reraising. Plus, you are not first or last to act, wich is the crappiest position in this kind of situation. If you are sure nobody has anything, raise more of shove. Minraising here is just silly.