My boyfriend is behaving suspiciously.

My boyfriend and I have been together for three months, and while things started off seemingly perfect (maybe I was a bit naive), I'm beginning to notice some concerning traits. For instance, he’s not a great driver, and it really worries me when I feel like he doesn't prioritize our safety. There was also a recent incident at a coffee shop where he spotted his ex’s car and didn’t want to go inside to avoid seeing her. I understood his feelings and went in alone. However, I later found out that he is still following her on social media. This bothers me, especially because he has spoken negatively about her in the past, describing her as "crazy" and detailing the issues that led to their breakup. Additionally, at the start of our relationship, he mentioned keeping pictures of his exes on his phone as sentimental mementos. I initially brushed it off, but it ended up bothering me. Even his friends advised him to delete them, which he eventually did after I expressed my discomfort. Another issue is that he often takes a few hours to respond to my texts or leaves me on read. His excuse is that he’s busy with schoolwork, or he prefers to reply only when he can give a thoughtful response rather than responding right away. There are more things weighing on my mind, but these stand out to me. What should I do?