As mentioned, there are way too many things that can play into this... Self diagnosis is often unreliable, biased, skewed, clouded...
But that doesn't mean you shouldn't consider your situation and what you might be able to do to help your situation... Even when under the care of a doctor, you should educate yourself... More than once I've had to demand appropriate care, or fire a neglectful med provider.
You are fairly young, and just married. Some of the most common issues with ED are tied to stress and mental blocks. So... How's that honeymoon period? Not as sunshiny as advertised? The first two years of my marriage were among the hardest... Not that it was all bad, but it takes a lot of adjusting sometimes to get into a healthy groove with marriage. The early highs are big, but so are the stresses, the ruts, etc... And studies have shown that often younger men with performance issues respond well to some sort of therapy.
Meaning you might need to talk to someone. Figure out where issues of stress are coming into play. And the worst part about mental blocks is that its self propagating... Trouble with performance builds up anxiety, which makes you less able to mentally relax, release... And reinforces the problem. Ugly cycle, and sometimes you need to talk to another person to find out where you can reduce stress and anxiety.
Workplace stress? Lots of hours? Money issues?
Are you exercising? Other studies have shown regular exercise to also help greatly with men having performance/ED issues. Are you overweight? Vascular problems? High blood pressure?
Drinking much? Smoking? Drugs? Medications?
Are you getting good sleep? Don't mistake hours of sleep for good sleep... A person can get several hours of lousy sleep and not be rested.
Eating well? Taking a good multivitamin? Good health can help in the bedroom.
What about her? Have there been problems getting her to orgasm? Can you get her there orally and then try to focus on yourself... At least so you can get a few "wins" under your belt and start to break down that mental block?
What about timing of sex? Is she responsive when you are most interested? This was an issue in my marriage... I'm a night owl, she's a morning girl. In the end, I had to compromise most of the time... Meaning I get sex less when I'm most primed, but she's more "willing", knowing my drive is higher and if I'm initiating sex at 5AM its because I'm driven and trying to meet her half way.
What about foreplay for you? Much attention is thrown toward the woman needing foreplay, and for good reason, but are you properly primed? I've found some lovers get too quickly to the point... Meaning they don't build sexual tension with the male... Its easy to become distracted by the males main errogenous zone... Its out there, hard to ignore... But personally, less attention to the mans member, and more attention to his mind, building tension, can pay off greater dividends, in my mind.
So... If you need different stimulation before sex, you need to figure that out and talk to her. If she's performing oral before intercourse, maybe that's too much too soon. The body is wired to experience the most intense sensations first, and then it dials those down a bit... Meaning too much play at your member might be making you less sensitized by the time you are ready for sex...
Do you have privacy for sex... Meaning no chance someone is going to walk in on you? You aren't distracted by the neighbors? Kids? Etc?
So... Stress... Physical health... Mental health... Environment... Many, many things at play here. It could be one issue, or any combination of the above summed together. Sometimes simpy a medication, or being overweight with borderline high blood pressure can do it... Sometimes it can be a little stress, a little less fit, a little older, a little less good sleep, etc...
So talk to your doctor. Your provider should talk to you about all the things I mentioned. If not, ask for a referral to a specialist who will be more focused on your potential problems.
Even issues like an imbalance in hormones, when you can ask to have checked, can cause this problem. Its why you need to educate yourself a little on what can cause this, then talk to a provider and seek out help. Not every solution to performance or ED issues involves a little blue pill. Unfortunately, too many people are too shy to talk to their provider about performance issues.
It happens. Talk to your doctor or find specialist who can help you put this issue behind you.