bf cheating? (kinda)

So I've recently been a little suspicious of my bf of him cheating..he's never done anything for me to break my trust before I the past. But recently I've seen him following girls on twitter/ig that I've never met or even heard of and I saw him follow one of those "finsta" accounts of a girl whose user was provocative and I've seen him texting another girl but I didn't want to snoop through his phone to see what they were talking about bc again the trust thing and it could have been about work but then I notice that he's been VERY protective over his phone and won't leave it alone with me. We've been dating for quite awhile now and I've talked to him about him following people I've never heard of and how I don't go around following a bunch of guys he doesn't know and he says he is sorry and it's girls he has played sports with and then I saw he unfollowed the finsta account after that talk. But Like I said I totally trust him but the whole being protective of his phone all the time makes me feel uneasy..