Is this some sort of weird game?

Before my ex and I split, he was friends with this older woman and I met her son who ended up helping my ex get a job. Basically, my ex turned out to be crazy and a cheater, so we split. Right after we split, two of my ex’s coworkers added me on Facebook (one being the older woman’s son) literally at the same time. I thought it was weird but didn’t say or do anything about it. Yesterday, one of them just randomly sends me a dot. I put a question mark and he claimed it was an accident. He said the dot was because he sat on his phone and it pocket dialed. I said “aren’t you friends with my ex?” And he started to say how he was adding people with mutual friends (but we had no mutual friends at the time he added me), and went out of his way to tell me that he knows who my ex is because they work together, that he just worked with him that same day, says that my ex has shown them pictures of me, how my ex said he “has a lot to think about”, and kept asking me if my ex was playing a joke on him. I feel like it is a game to get my attention or something because my ex loves playing mind games. But idk if I just sound paranoid