Hi and thanks for the query.
This is not a simple issue. Ejaculation and erection are complex pathways that require a lot of evaluation before a cause can be identified. In brief, there are two types of problems, organic ones and inorganic. The inorganic are the psychological ones where a mechanical cause can not be identified. But the rule is to rule out all the organic problems first.
I would suggest that you have the Urologist evaluate your problem in detail. Diabetes and high blood pressure can inflict changes in the circulation and nerve endings of the penile area causing problems with both erections and ejaculation.
While, the urologist completes his/her evaluation you should also see a sex therapist and a psychologist to save your time and evaluate the psychological aspect side by side.
I do not suggest that you skip or leave your blood pressure medication in order to search for a cause, that might cause more harm than good.
The urologist can run tests like nerve conduction studies, spinal xrays, artificial erection test, ultrasound of the scrotum and prostate etc to see where the problem really is. Central or in the apparatus itself.
Let me know if you have any queries regarding this.
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