Cumming... Jizzing... Ejaculation. Whatever you want to call it

My boyfriend (age 16) has never ejaculated... We're sexually active but he never finishes. 
In fact he has never ejaculated on his own either (like through masturbation)   
But he has had wet dreams and there's precum a lot of the time. 
I'm just so confused, as is he, should he be worried? 
Anyone have a similar experience? :/ 

Glow Resources

Let’s Glow

Glow is here for you on your path to pregnancy

Glow helps you navigate your fertility journey with smart tools, personalized insights, and guidance from medical experts who understand what matters most.

25+ million

Users

4.8 stars

200k+ app ratings

20+

Medical advisors