Hi,
Welcome to icliniq.com.
At the age of 30, the neurological illness, diabetes, and hypertension are not common. So mostly the cause is anxiety and stress for erectile problems.
Stress and worries can make a person distracted even while masturbation. When a person watches a porn movie because of the visual content, a person cannot have much distraction but when a person is doing masturbation or sex, he may have distraction because of stress. In addition to this, stress and anxiety can cause low sexual desire.
Financial issues, work load at job, daily hustles, conflict with spouse, repeated worry about failure in bed and partner satisfaction are the main reason for psychological erectile problems. These are the sources of stress.
What you have to do is forget about the past failures and make a new beginning, for initial four to five encounters in sex you should not go for penetration and just enjoy the foreplay. Spending more time in foreplay helps in holding erection for longer. It also helps in identifying the sensitive areas for arousal in your partner. The sensitive areas in female are neck, nipple, clitoris and anterior wall of vagina. During foreplay, you have to concentrate on these regions. After four to five sexual encounters without penetration you can start intercourse and with prolonged foreplay, take help from your partner for holding erection longer like oral sex and masturbation by your partner or whatever she is comfortable with.
If you are not confirmed about your morning erection then you can perform a bedside test like a paper test. In this test you have to apply a strip of paper [about 1 cm] around your penis base while it is in the flaccid state. It should be tight enough and use gum to stick both the ends of paper around the penis base. When your penis gets an erection during the early morning, the paper will be ruptured and this will be the positive finding that it gets normal morning erection.
If you are depressed then take a visit to a psychiatrist and get treated with antidepressants. You can visit a good psychiatrist or sexologist in your city and undergo sexual counseling and therapy.
Bupropion can help in increasing your libido. Continue it. Other drugs that can be used for the same are Pramipexole, Cyproheptadine, etc. Pramipexole can be started at a dose of 0.125 mg three times a day. Dose can be increased to 0.25 mg three times a day after one week. I suggest you to continue Bupropion and wait for one month. If you do not find any improvement then change to Pramipexole.
There is no need to worry about circumcision, it can cause this abnormality or decrease sensation in penis glans. More you ruminate about having a problem, more will be the actual problems. For anxiety purpose, yoga and meditation will be helpful along with jogging or walking.
I hope this helps.