blowjobs

Ladies, I need your help. So I recently have started becoming intimate with my best friend. He's so amazing and treats me well. We're both virgins and everything we've done has been new for both of us. We're 18. He's only fingered past girl friends. But I tried giving him a blow job. I've read past posts on them but I'm missing something. He says that it could be that he just has an erection problem. He said he didn't feel any pleasure from me. He appreciates me trying and wanting to please him. Because I really want to please him. I use my tongue, I suck, I lick, I tighten my lips, don't use teeth. Can you help me determine what I need to do to help him out? I've asked him and he tells me what to do, but still nothing. I just can't help but think I'm terrible at it.