A rule of thumb I use is this: If I’m having sex that day, no masturbation. I may do limited PE. If I masturbate that day, limited PE just because of time and fatigue constraints for the next day. As masturbating and PE can fatigue you for some of the following day for sex.
If I’ve rented a hotel room or will be doing so then I don’t do PE or masturbate for at least 2 days prior. Because all day sex can be hard on the body and definitely will knock the life out of a penis by design.
If you are having marathon sessions daily (I’m jealous *smirks*) I would move to lighter equipment and routines if PE is still a priority. There is a philosophy of “Less is more” and 15 minutes a day still counts and adds up, depending on what you are doing and how intense it is.
Do not stress, just be easy with it. A good mindset makes small sessions fun and productive. PE shouldn’t be work and you shouldn’t feel a “need” to put in 3 hours to get progress. Just do it if you want to. That way, you make time for sex and progress without stressing yourself or your unit beyond what’s needed.