Abu Hurairah radiallahu anhu reported that the Prophet peace be upon hi said, “A strong believer is better and dearer to Allah than a weak believer, and there is good in everyone, but cherish what gives you benefit in the Hereafter and seek help from Allah and do not lose heart, and if anything (in the form of trouble) comes to you, don’t say, ‘If I had not done that, such and such thing would not have happened,’ but say, ‘Allah has ordained it so, and whatever He pleases He does,’ because the word “if” (if only I did this, etc.) opens the door for Satan.”
Indeed, you can not control what will happen within the next hour nor can you change what happened during the last hour but the present moment is within your grasp. Rather than focusing on “what-ifs,” focus on “what is.” Pay attention to the blessings surrounding you - the feeling of the breeze on your face, the taste of the tea on your tongue, the sound of birds chirping nearby. When you choose to be mindful of the blessings that surround you in every moment of everyday, you will naturally start to find that you tend to feel calmer and less bombarded by anxieties about the past and future.