As a ciswoman, I concur with Sydney_NYC. The clit can get hard & erect like a little engorged pebble. Then sensation can range from uncomfortable to somewhat painful depending on how aroused it is. When I am aroused normally, it is just a bit bigger, but the more the state of arousal rises, the more engorged it becomes with blood, and it can be quite firm (like a pebble) and even be painful. The plus side of this pain or discomfort that it usually means a more powerful orgasm. I don't usually hit the superstate of arousal, but when I do, it is oww, then WOW! In my opinion it is a good thing that you are having these sensations. I wish you the best.
PS- I know you were asking for post-op replies, but I felt you should know that ciswomen have a similar reactions. But there is no harm in checking with your surgeon just in case. My daughter will hopefully be having her SRS later this year, and although I would tell her that my clit reacts that way, I would also tell her to talk to her surgeon just for peace of mind. You only have one body, take care of it. There are no silly questions. I am very happy for you & your surgery. Continue to heal & enjoy your new body.