Being creeped in my own apartment

Hi and thank you for reading. I guess I just want to see if someone has been through a similar situation and if anyone has advice to share.

I'm a 33 year old woman living alone and i've been in my downtown apartment for over 4 years. It's a development of a few towers and there is one in front of one side of my apartment. I have a corner unit with floor to ceiling windows. I've never really noticed anyone in the other building, I'm really focused on my life and the views if I ever look outside, it's quite stunning.

A few weeks ago as I was coming from the gym, a guy talked to me in the elevator saying he was my neighbor from the other building, asked if I worked out, etc. I didn't think anything of it as I'm used to guys trying to find opportunities to talk to me. I tried to keep the conversation short.

Today, I was heading out to run some errands and I passed a guy I didn't recognized. I had my headphones and I was walking fast. I noticed a block away from my building that I guy was trying to talk to me. I removed my headphone politely and responded to his questions. He kept walking with me and told me that he knew I loved on what floor, in which apartment, he was watching me.

He asked for my phone number, I said I had a boyfriend and that it wouldn't be appropriate. He said: "you don't have a boyfriend, you are always alone". It f*cking creeped the shit out of me. Anyways, I held my grounds and said I didn't want to give my phone number because I was in a long distance relationship. He said he wasn't done and would keep trying to get a way to reach me.

The fact that he looked at me so much from his balcony that he can recognize me in the street is wild to me. I couldn't event tell you who lives in the apartments that I see in the other building. Like I wouldn't be able to tell you if they're women, mens, single, couples, etc. does he use binoculars? Lol 🙁

I was gone mostly away from mid May to mid September and was just back for a month. This guy is new to the development and I'm scared to see what's next since he said he would keep trying. Moreover, I don't feel safe in my apartment, I've been hiding in my room the rest of the day, I'm scared to go in my kitchen to eat.

Am I overreacting? I'm kind of trying to play it cool, but I feel like my personal space is violated. I'm used to having creepy guys at work, at school, in public transport, bars or hotels where there are staff and other people around which makes me feel safer.

How do I go about this? Who can I notify if I feel scared? Do tenants have any recourse? Has anyone been in a similar situation? What can I do to be safe? Where can I get mace 😩

Thank you all for reading and for any response. 💜