I agree it is good to stand up for yourself. Calling the police can be a little bit like the kid being picked on in the school yard telling the teacher on the bully. I'm personally not a fan of the police most of the time. I believe what they are meant to stand for is good, however, I also believe a lot of cops let the power to go their heads (several time I have seen police run red lights without their lights on, I have been stopped while walking in the pouring rain in the middle of the night to be mocked by them, and there were two cases in my town in one month of cops shooting dogs for merely barking at them, not even attacking).
They represent protection, which is what they are meant to be. They are supposed to be protectors of the innocent and the law. Calling the police shows that you are serious about a matter. It's showing a symbol to show the level you're at, essentially.
I had a roommate problem. Every morning he would come into my room and scream at me because he said he could hear my cat walking at night. When I say morning, I mean anywhere between 5 and 7. He would scream at me for walking in from work, for anything. He called me names, he threatened me, he threw my cat's litter box, food dish and water bowl off the balcony, and he made me terrified to be in my own home that I had welcomed him into when he moved in. I went to the police to sort it out because I couldn't do anything else. He was bigger, much older, and stronger than me. The police told me they couldn't do anything about it. He wasn't doing anything illegal, and they gave me a number of a mediator.
When I went the police, I didn't really want them to do anything about it, I just wanted it on record that I made a complaint against him, that I had gone there afraid, in case he did anything more than just scream at me and throw my cat's belongings around. I went to them to essentially create a record, which they didn't do either. They didn't take his name or my name. So it was a pointless venture, but it was the only think I could think of to do.
I also didn't tell them I wanted to create a record or file an official complaint against him either. It is however another reason to go to the police. A record of an event that is mildly getting out of control now can probably help you in the future if and when it's really getting out of control later.