HELP what do I do??? Sticky boy situation 🥴

Hi!!! So I have a situation that idk is an issue or not. For some backstory, I have had a long term boyfriend, David, for about two years now. I love him a ton, and he is my best friend! I am a junior in HS and he is now a freshman in college at a college in my town. Just in case someone comments on age difference; we are RIGHT at one year difference in age. (he is young for his grade, I’m old.) There is a guy, John, who moved away from my hometown to another state a couple years ago. We were in a friend group and close friends for all of our schooling. We keep up with each other through social media profiles, but aren’t really friends anymore. The last year John lived in my town I had a massive crush on him. I always thought and was told by friends there might’ve been something there from him as well. But, I know we were super young then and that is not super reliable. Once he moved away, I got over him relatively quickly & moved on. I didn’t even really think about him for a solid year. I heard he was coming to town a couple months ago and suddenly he was all I could think about. My mind filled with stories of how maybe someday if David and I broke up. My biggest problem today is that I dreamt about him last night after not thinking of him for maybe about a month. In my dream he came to town, (he does probably a couple times a year, the last time I saw him at a restaurant with my parents but never hung out with him, like with friends not alone lol !) and he saw me at some event and kept saying like “if theres something anyone wants to tell me” hinting at me. Later in the dream he kissed me. I told David that happened.... and he basically just said well if he kissed you and you pulled away its ok I forgive you. I don’t like having these feelings because I love David. He is awesome & I would never actually be unfaithful to him. What does this mean/ what do I do??