Masturbating and not loosing hard on

im 17 year old who masturbates ever day atleast 5-10 times if not more since like 10 and i dont know if its normal or when it began but i can orgasm and ejeculate and then keep masturbating and having orgasms after 1-2 times there is not much seamen but even after 6 or more orgasms i can keep going unit i dicide its enouth or feel like i realy need to stop other wise i would do it for hours like i done many times but i dont lose errection unit i stop the last time i lost errectionm that i can remember was like 2 years ago when i went at it for hours and i became all sweaty but even then i managed to raise my penis from totaly done to hard thats 1 of last times i ever had problem with loosing errection whout being done or wanting to stop but now i just got used to just having few to many orgasm and stoping when i think i wasted enouth time or feel satisfied with atleat 5 orgasms it rarely 1 orgasm and if it is its only for a minute before i get turned on again turn to porn tab and do it again