Creeps

So I had one of those creepy stalkerish situations taking my son to the library today. We were walking in and this guy was leaving, I noticed him right away bc he was creepy looking and generally didn’t look like the type of person I see there. He turned around right behind us and started walking back in...I moved aside with my toddler to let him pass, bc weird....he went one way and we went into the kids room, 30 secs later he came in and sat at a kids table and got on his phone. More kids started coming in so it just got weird for a grown man to be in there alone and he left the section. 30 mins later we were leaving, as soon as we exited the kids room he was right there starting to walk up a set of stairs. I got to the front door and just turned around to find him bc no way I was leaving if he turned around again. He was upstairs in a loft area staring down at us. Every time we saw him he was just looking at us. No book bag, never looking at books, just wandering around and staring. I ran to my car and took the most ridiculous way home, called my husband in tears....you know the gig. Anyway my husband thinks I should have reported him and even now still thinks I should, I would have if it went any farther but I really just wanted it to be over. What do you ladies do in these situations that leave you feeling so unsafe but nothing actually happens?