Is he cheating or am I paranoid?

Hi ladies. Lately my almost 4 year relationship has been struggling. My bf is going through a tough time with his extended family and it's been taking a toll on him and affecting our relationship. His mind always seems far away. He's just not acting acting the same. Now he is a really good man to me, we get along well, we always communicate and work out our issues and I would say that we dont have any major problems. About a months ago he started a new job and 2 weeks in, he was asked to go to another Island for a quick business trip. The way I was informed about the trip had me a little bothered but then again I know that's how some companies operate. He informed me some mere hours before the flight, via phone call that he was asked to go to handle some company business and he was leaving such and such time. So I wondered if he knew before hand and didnt tell me or if they actually sprung that on him? Now he hasn't really given me reason to distrust him but you never know. I dont want to he naive. His business trip lasted 3 days and on the last day, he was talking to me on the phone and told me to hold on, I stayed on the phone for like 5 mins before I hung up. He didnt call back right away but he messaged and told me he would brb, he did not give me a reason why. He then called like 30/45 mins after and I asked him where did he go. He responded with a question.."where did I go?" And then he said he went to the airport to pick up another guy who just came in on some business too. I simply said okay and I left it. So today were we at the gym and after our workout I needed to make an important phone call. I had no credit on my phone so I asked him to use his. He unlocked his phone and cleared all his opened apps and then gave me the phone. So I asked him why did you need to clear the apps? And his response was "I always do that everytime I unlock my phone". I said nothing. Now my fingerprint is stored in his phone and he knows the password to mine. We dont hide from each other or so I hope. When I got home I brought it up again and I said "well given my fingerprint is in your phone, I can unlock it myself and make the call, why didnt you just give me the phone?" He said nothing. I'm so bothered right now. I found myself overthinking. I realized he would always keep his phone on the opposite side of me. I have gone through his phone in the past and I didnt really find anything but idk. I find his behaviour was a bit shady. I know he has intentions on proposing to me before the year is over and I dont know if he cleared his apps because he didnt want me to accidentally see something regarding that. I'm not sure. I dont know what to think. If he is cheating on me or talking to someone else I'll be devastated. I don't want to come out and ask him directly if he is because I dont want to seem crazy but I'm not quite sure what to do. Please any advice will be appreciated. Thank you!