hi Mirko!
I wrote something similar about the subject before.
Yes,I tried(up to 10 actually),and in a row day after day at least 3,4 time per day.(I was in that period addicted to sex/masturbation,and all the time under P.O.I.S)
I notticed that in my case with every new O I felt weaker physically and more sad/deppresed but not in a fatigue way,more like when kid can't find way to home,that hopeless felling.(I am sorry for this term,I don't know English word for that.)
Recently I discvered that as a whole I maybe even feel better after few O's in a row,calmer and very motivated to do useful and creative things(usually I can't feel any pleasure or satisfaction), despite simptoms mentioned above and Pois in general.
Before it was not like that but recently durring my research for relief method I had more O in last two months then in a two years before,so that might be just effect of relief methods I am experinenting with ,or maybe after multiple O's I am simply skower and more "switced off",so there is no that feeling that I am hoplessly borred,or that deparete fatigue feel in the cheast and throath.So idk anymore.
I almost forgot to mention that in last 2 months I also notticed that I kinda feel more clear minded and more emotionaly stable then after just one O,so wak,with stronger headache,but less emotional and some other symtoms. I am not 100% sure about that though,simply coz when in P.O.I.S I can one second feel something and in 2nd something completly differente.
Just to mention,unfortunatelly I didn't have much succes as I expected with relief method experiments
Sorry for long post,and take care my friend!