Hi,
First of all, it is not your fault and you don't need to feel guilty about it. It is a smart thing you did that you are reaching for professional help to better understand the situation.
Delayed ejaculation is when a man is not able to reach orgasm and ejaculate after 30 minutes of penetrative sexual intercourse.
It affects 1-4% of men. So it is not that common.
Premature ejaculation is way more common.
Reasons can be physiological or psychological. Physiological causes are: Drug side effects: like anti-depressants, or alcohol.
Stroke.
Nerve damage. Psychological: Suppressed feelings, early childhood trauma, refusal to enjoy pleasure, fear of
pregnancy.
Since it is your first time to have sex. I think it is natural and I think it is performance
anxiety. I would not make a big issue out of it for the time being.
Try see how it goes with time after having more sexual intercourses. Try not to push it and let it happen naturally in a safe understanding environment. It will get better. If it doesn't like after 3 months feel free to contact me again to discuss further.
Hope I have answered your query. Let me know if I can assist you further.
Take care
Regards,
Dr. Ahmad Nazzal