Should I be worried that it’s hard for me to ejaculate while masturbating?

So I’ve been masturbating since I was about 11 or 12 years old, but instead of “jerking off” like many others do, I lay on a surface, but my hands on my penis, and put pressure on my penis. I usually do this with my underwear or shorts still on. But all of my friends can jack off and ejaculate he normal way, but I can’t really do it my way. I sometimes see some dried white spots on my penis, but I’m not sure if that is from an ejaculation or not. Usually my underpants get kind’ve wet and one time I remember there being  a wet spot on my bed after I masturbated my way, and I think this may have been a ejaculation but I’m not exactly sure. I’ve tried to stop masturbating this way and started to use my hand but I can’t find pleasure from it unless I push down near the bottom of my penis (near the pubic hair) and I can’t really ejaculate. So the questions I have are:

1: How do I know when I ejaculate?

2: How should I start masturbating the “normal way”

3: Should I be worried about any of this?

And just a little extra information to help answer the questions; I turned 14 about a month ago, I have armpit hair, pubic hair, and I’ve had a voice change, so I seem as if I’m going through puberty fine. I’m just worried about my ejaculation.