Help! Am I overreacting to my male coworker’s behavior?

So, I’ve been dealing with this male coworker who has been making me pretty uncomfortable. He hasn’t done anything big (yet) but the things he does I feel are crossing boundaries.

I experienced some pretty extreme sexual harassment from my boss at a previous job, and I know that experience has made me hyper-aware and sensitive to any odd behavior from men ever since. This nothing compared to that but it’s still making me uncomfortable (maybe because of bad past experiences?) Because of that, I need an outside source to tell me if the things that have been going on here are just my coworker being nice or if it’s something I need to do something about. This just feels so small but I don’t like feeling anxious at work. I’m also very unconfrontational and I’m not sure what to do about these things. Here are a few things that have happened:

1. He made a sexually explicit comment about me one day. I said “F-me” and he, under his breath, said “sure.” He didn’t intend for me to hear it and laughed at another one of my male coworkers and left the room before I could say anything. On another incident someone threw something that hit me in the chest and he had to point out that it “hit her in the titties.”

2. On several occasions he has come into my office and sat down just to talk about stuff, like get to know you stuff, not work stuff. Not casual conversation, but he shared with me that he is okay with polygamy (he’s currently married, supposedly anyway. I haven’t been able to confirm it and he never talks about her, doesn’t wear a ring, just doesn’t act married at all but who am I to judge), and talked about his sex ed in high school. Asked me lots of personal questions which I tried to skirt past. One time he came into my office like this and there was nobody else at the office at all… I’ve started getting to the office earlier so I’m not there alone with him ever and when he tries to come in and talk about non-work things I stay facing my computer and act busy. Sometimes that just prompts him to walk up behind me and put his hands on my chair while he talks about work or whatever.

3. He has been warming up water in the breakroom for my tea every day. And he wants to make sure that I know it was him. Instead of just doing it, he has to point it out to me every single time that “there should be warm water for you!). It got to the point where I just started bringing tea from home to avoid this situation.

4. I made a casual comment about it being cold in the office one day and he insisted that I take his jacket. I declined.

5. He interrupted a personal phone conversation between myself and my husband and later asked me if everything was alright and that I seemed down when he popped by my office. Like, I don’t need a shoulder to cry on! (nothing was wrong anyway!)

6. I catch him staring at me almost every day which is super awkward. Someone else will be talking in a meeting and he’ll just be staring at me until I make eye contact with him then he looks away.

I’m a happily married woman, and I’ve made that extremely clear to him. I just feel like his behavior is disrespectful of that and I’m not sure how to confront the situation since he hasn’t blatantly done anything and nobody has witnessed most of this.

Can someone tell me if I’m overreacting to his behavior? It’s gotten to the point where I just hide out in my office all day and avoid social work conversations with anyone. I need advice on how to handle this situation! Should I say something to him? To someone else? Should I just ride it out and see if it escalates? I’m afraid if I say something to him he’ll just say “oh, no! I’m just a nice guy I thought we were friends! (I know how guys can be.) Am I making something out of nothing? Would this bother anyone else? Help!