Hi WanderingVagrant,
First to introduce myself - I too suffered a penile injury about seven years ago, while I was in my early 20s in university. Not to freak you out... but I'm still dealing with it...
I missed any window I might have had after I injured it. I can't say what is going on with you physically, but for me scar tissue formed. But perhaps if I acted in the earliest of days, I could have prevented some of it from forming! Maybe. If possible to prevent scar formation, do it!! Look it up, how to do that! I've heard of PRP injections (which is invasive though). Perhaps supplements if nothing else, perhaps Serrapeptase - but I really am not qualified to recommend this product or other specific supplements. If there is still bleeding I don't know if that changes what to take. But if it's possible to prevent scar tissue from forming, try.
The reason scarring is terrible in the penis, is that scarring in the tissue prevents the penile tissue from expanding to some extent or another depending on how much scarring forms. Healthy erections work by the blood rushing into the penis, expanding the tissue, the tissue expands to "pinch" the veins shut. Veins return blood from the penis to the heart, so with the veins such, the blood stays in the penis, allowing you to be hard and maintain an erection. If the tissue can't expand, the veins are left open, and blood can't be trapped, thus an erection is soft/not maintained.
And there are treatments you can try to reduce or remove scar tissue - experimental treatment - maybe more proven treatment that I don't know about - but it's still a big issue of how exactly do we remove scarring. The years go by, and I'm looking. So better to prevent it from forming in the first place.
Injuries can also cause localized blocked arteries. There is bypass surgery.
Medication, like Viagra, can compensate for the above to an extent if the above is minor enough. If it is major, the Viagra won't be enough.
I believe what you have is a physical issue. I hope it heals and bounces back without the need for intervention. But tackle this. Good on you for already posting 5 days out. See a urologist asap. And also know that not all urologists are equal. If they say wait 6 weeks and then come back, find a new urologist, or get a few on the go. If they say it's in your head, maybe question how they reached that conclusion from doing no tests? Etc. Good luck!