In my opinion, if you have only had him for 3 weeks you should have let him have tie to acclimate, like a week or two to settle in, then feed, wait two days and handle. The most important part of handling a snake is spending quality time with them. Quality over quantity! For example, it doesnt matter if you hold them 5 times a day 5 minutes each, because thats added stress of changing environments and handling for short periods of time without letting them get used to being held. Instead hold him for 1-2 hours, dont take them out unless you have the time to put into them! Let your snake get used to you and its surroundings, and showing them you can be trusted. Especially since your snake is young, its very important to form these good impressions now, especially about handling. This means light handling while still firm enough they feel supported, and giving them a limb to curl around, imagine youre a branch of a tree! Even just letting them ball up in your lap or on your chest, a warm place in your body while you watch a show or play a video game, like mentioned above.
Quality time with snakes is so important! Remember your snake isnt just a pet, but a partner! they live for a long time so you have to be patient and respectful in building a relationship. My ball python, Ravioli, loves to watch me play video games or watch movies and shows with me! We are best friends and i usually can tell exactly how hes feeling from looking at him, hes very polite about asking for things. With the amount of time ive put into him, he knows he can trust me and ill listen when hes uncomfortable or doesnt want to be held or wants to be put back. Patience and listening is key with these kind animals
Note on the poop/urates, if your snake doesnt strike its ok to take them out of their hide to remove the poop, just watch for signs of stress. Its usually best to wait until theyre out of the hide though (this will be at night for ball pythons, so if it means staying up later than youre used to im sorry but as they get more used to you, you can take them out no problem. You can also combine cleaning with holding time so youre not just taking them out and putting them back in. find what works best for you and your snake!)
Best wishes! I hope you two become good friends! and dont be afraid to ask for help online, good on you for coming onto a forum!