Am I petty for being mad?

So my boyfriend and I live in the house he owns. There’s only room for one car in our drive way, so he parks his truck on the street outside of the house. Several weeks ago, a couple moved into the house two doors down. They have a storm grate in front of their house, so the woman started parking her van in front of our house where my boyfriend has parked for over a year. The houses in our neighborhood only have driveway room to park one car, so families park their other cars on the street in front of their houses so it’s hard to find a street spot besides in front of your own house.

The other day my boyfriend and I got home first and parked in front of our house, so this woman had to park in front of their house on the storm grate. We left for 10 mins to get food and she had come outside just to move her van into the spot that he always parks. We had to partially block our own driveway to park his truck.

I know the street is city property so whoever can park on it and we don’t own it. Is it petty to be aggravated? What would you do?

IN ADDITION: if he gets home first and parks in front of our house, she will literally try to squeeze her van in behind him when only one car can park there. Her van will be touching my boyfriends bumper and she will be blocking part of this old lady’s driveway (old lady lives in between our houses)