Brief Answer:
you should get it checked by a Urologist in the first place...

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concern...

Please note, although it's good that there's no pain around the area, there's some minor bleeding evident after injecting Trimix. However, if you notice any visible swelling(even a minute one), any increase in the size of the bruise, numbness/tingling around the area then you shouldn't wait any longer and simply report it to your treating Urologist.

Now, if this was your first time injecting the Trimix then I'd definitely recommend a visit to the treating doctor just to make sure there's no injury to some of the penile blood vessels (these are extremely delicate structure and should be addressed quickly in order to avoid any secondary complications).

If this was not your first time injecting this, then you must be trained by now, however, in that case, it's advisable to wait and watch for another 24-48hrs for any of those above-mentioned warning signs (after the injection)...

To summarise, not to worry, but please wait for the time being (before administering any further dose) and get it checked by the treating doctor in the first place...

Let me know if I can assist you further.

Take Care
Kind Regards

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