PEVR – Perceived Ejaculate Volume Reduction, a condition when you notice that you are ejaculating a lower volume of semen than usual. This can be because of frequent sex or masturbation in a short time. If this is the case, there is nothing to worry about. You need to give your body some time to produce good amount of semen and sperm.
If you are seeing less volume of ejaculate even after a gap of good number of days, please see your sexologist to make sure everything is alright.