Anxiety due to being stalked, how do I calm myself?

I’ve been stalked multiple times in my life, but for some reason I have a ton of anxiety after today.

Long story short, I was in the grocery store and this man was following me around and making eye contact. He ended up leaving the store right behind me with no groceries. I held my pepper spray in my hand and made it to my car. I drove home and made sure no one was following me.

I was in fight or flight mode and didn’t even think to contact authorities. What if he stalks someone else who isn’t as aware as I was? What if he actually did follow me home? What if he saw my license plate or something?

It’s now midnight and I’m laying in bed. Every time the house creeks I jump. I keep thinking I see someone in the corner of my eye. I feel nauseated. I’m scared. I’ve locked all doors and windows.

I have left over Ativan from a recent surgery at my dads, but I don’t want my dad to worry or lecture me. I also don’t want to rely on medication for anxiety. What should I do?