Does my ex boyfriend still have feelings for me?

I dated a close friend/colleague of mine about 7 years ago and the relationship ended when I questioned him where we were headed. Needless to say, he wasn’t ready for a relationship so I ended it even though I had very strong feelings for him. He kept calling and texting me about 2-3 weeks later after the breakup and I completely ignored him. Sometimes he would call 3 times a day and leave messages on my phone. He did this for about a few months and I ignored all his calls, texts and emails. At that time I met someone new who knew what he wanted. Long story short I got married (to the guy who knew what he wanted) about 5 years later and found out that my ex had gotten married just a few months before I did.
Since we all work in the same industry (me, husband and ex) we run into each other often. I started running into my ex about a year and a half ago at business related events. To break the ice I sent him an email asking how he was doing. I then saw him at an event and he mockingly told me he got my random email in front of another colleague. Then he mockingly asked what my new last name was. All the while his face was bright red with a huge smile. I noticed he would show up to these events more and more and try to act like I was invisible, but I could tell he was looking at me from the corner of his eye. He would send me emails inviting me to more events and even gave me huge complements me via email when I left a horrid job. His body language is odd.. when he walks in a room he immediately makes eye contact with me (not on purpose) and his face turns red. I’ve even caught him staring at my wedding band a few times. He’s also made an extra effort to be friendly to my husband.
One thing I regret is completely ignoring him because now I wonder what would have happened if I still kept in touch with him. We have great chemistry and he always made me laugh. I love my husband dearly, but I hate this “what if” state of being. Does he still have feelings for me or am I dillusional?
Sorry I wrote so much!!!
-Anita