I've had some PE issues in the past, and still do occasionally.
I do blame porn a bit for it. Watching porn can be very much about just wanking and cumming quickly and not doing all the things that are fun together in a bedroom. If you're into it try things like RO or massaging her or just kissing before you get to the BJ or HJ or penetrative sex bit. Also try to think about communication with the WG, tell her to go soft and slow with you. Can lead to varying degrees of success, but worth a try IMO. A good punt for me could just be a lot of light foreplay and kissing that leads to a quick bit of sex and a quick orgasm. But I always try to enjoy the build up and the tease and not focus on getting my orgasm too much. Lastly don't beat yourself up about it. Be thankful the bloody thing works and just try to enjoy it even if it is over faster than you'd want it to be. You might think a lot of women want a guy who can last for ages before cumming, but this is actually a bit of a misconception IMO. A lot of woman will take pride in being able to make you cum quickly, a lot of them enjoy a quickly just as much as us, and often the quicker it's over often the better for them, especially if she's a prossie. Means less work for them. I mean, look on the bright side, you have the option of just doing 15 minute quickies if you want and get you orgasm and save yourself a bit of cash in the process, sometimes wish I could do that and be sure of getting my orgasm.