Blowjobs...

So I've only had one other boyfriend than my current one and he's the only person I've given a blowjob to. He was my first and his experience with them in the past wasn't too great so I wasn't that worried whether I did a bad job or not cause he hadn't really experienced a good one. I could never make him cum from just a blowjob. He said I was good at it but he always said it was cause he needed to be going "fast" in order to cum. When we had sex he wouldn't cum unless he was going really fast too. So idk if he was being honest when he said I was good at it or just told me I was to spare my feelings.

Now I'm with my new boyfriend has more sexual experience than my ex and myself so I'm super worried that when the time comes I'm gonna give him a really mediocre blowjob and he's not gonna cum and it's gonna be super embarrassing and awkward

Advice??