Q: My lady and I have been having trouble lately; I can't seem to last as long as I used to. This has never happened to me before. What should I do?
A: The first thing you should know is that this is normal.
The phenomenon of not performing to your usual standard can be pretty distressing though, especially when you don't know why it is happening. There is so much stigma in our culture around men discussing concerns of health - especially sexual functioning. So. What is the reason?
Short answer: it depends.
There are a wide variety of terms that explain different phenomena of sexual functioning: premature ejaculation, low desire, erectile dysfunction, delayed ejaculation, substance/medication-induced sexual dysfunction... It can all be fairly confusing to figure out on your own.
Below, I've included some questions to consider so that you can be aware of how your body, environment and relationships may be currently interacting. This list is not exhaustive. It is simply to give you a starting place so that you can knowledgeably discuss your situation with (a) your physician, (b) a (sex) therapist, and (c) your partner.
Which Aspect Needs Improvement?
Does your body produce an erection when you are mentally ready for sex?
Are you able to maintain an erection throughout partner stimulation?
Does your concern occur every time you have sex, or only some of the time?
Note: the normal range to maintain an erection during active thrusting is 3 - 5 minutes
Do you have an especially strenuous work schedule?
Have you been getting adequate sleep each night?
Are there currently any stressors in your relationship? Or family?
How long have your concerns been present? (weeks? months?)
Long-standing Have you witnessed or experienced any traumatic or disturbing events? Has your partner?
What is your history of porn use and/or self-stimulation?
Have you been in a relationship that involved cheating?
How old are you?
When was the last time you had a check-up at your doctor's office?
Have you recently had any injuries or surgeries?
Have you experienced symptoms of a depressive mood within the past 6 months?
Are you taking any new medications?
Does your partner pressure you for sex or make demands that you feel are unreasonable?
Do you feel comfortable or ready to engage in a sexual relationship with your partner?
Again, this list is meant only to help you develop the language to talk about your concerns and needs. A physician and qualified relational therapist will be able to help you interpret these answers in order to find a solution specific to you. Google is helpful for knowing you are not alone - but also, remember that every situation is different.