I have the opposite problem. I'm in my 40s and still have problems with pre-mature ejaculation-- especially when with someone for the first time. There are times I envy those who can't finish or take a long time to cum.
Like the OP, my problem impacted my sex life in and out of the hobby. Out of the hobby, I simply had zero confidence in myself. In the hobby (before discovering GFE providers), I was left many times with unsatisfactory experiences. I would barely be undressed and she would just barely touch me. I would cum. She'd put her clothes on, and that would be it because that was back in the days of "one and done". Thankfully, I stopped trying to fight it. Instead, I sought out providers who allowed or even encouraged multiple pops. Also, I learned to slow things down a bit and vary the pace and types of activities. Now, that I'm better attuned to my body and how it reacts, I'm in control of an encounter instead of the encounter being in control of me.
My recommendation to the OP is this. First, what are you seeking? Are you turning to providers to relieve your sexual tension, or do you really want a civie relationship that works for you? There is "no" age requirement to be a client in the hobby (other than being 18). If you really want a regular civie relationship with the full sexual experience, the hobby is probably not for you. If you are wanting to experiment, gain confidence, or get to know how your body works in response to sexual arousal, then the hobby maybe a good way to seek your sexual release without all the hang ups of getting into the emotions of a relationship. It really is up to you. But I will say this. Regardless which path you go down, communicating your situation is key. If your partner (be it civie or provider) has no clue as your "finishing" problems, both of you will end up being frustrated. Also, you do need to find what actually gets you off and to know those signals or tells. Once you know this, tell your partner. She can then focus on satisfying those sensations. If you do seek out a provider, talk with her ahead of time. Let her know your issues. A lot of these ladies will take it as a challenge to get you off
Finally, find one way that you know will get you off. Maybe it is a hand job or a blow job. There's nothing wrong with having mind blowing sex in a variety of positions and then blowing your load at the hands of a lovely lady.