Hi, welcome to POIS center. Many users here are experiencing what you are experiencing. Mine is psychological symptoms, yours seem to be physical.
You're 29 and you just started masturbating? Or was that a typo for 19...
Yes, sex will have the same effects. As long as there is ejaculation, we will have symptoms of POIS.
What I use right now, is niacin, it combats the symptoms enough for me to go through the day... doesn't work 100% but it's something.
Stay put, and maybe we'll find something to help us together.