I have been in a 2 year relationship.

We have finally gotten out of the honeymoon phase. Since we had more trouble when communicating things that have been bothering us for a while. It has been hard since we work long hours . Plus I also go to school . 3 weeks I have made it aware of some of the issues that we need to talk to . We have just started to barely communicating on what had been happening and try to fix it . We talked about having respect for each other when it comes to being faithful to each other. We also talked about the future and not being afraid based on other factors. After having this conversation I noticed he was following a girl . I am not sure if I am overthinking? Since he is always saying I can check his phone and always leaving his phone when going to the bathroom.Since he has always taken care of me and always paying when going out . He is always coming when I have a flat tire, bring me coffee, and other nice gestures that show that he cares . Plus I have his location.