Yes, start injections at least weekly with bimix or trimix. They will probably start you at 10 units and you can work up or down from there. There should be no negative issues from proper injection therapy. You will need your urologist to prescribe and they will likely want an in office exam and test run.
In my opinion injections were really painless. For many men, they get crazy hard long lasting erections. It is really important that you get an erection as often as possible to keep things stretched out and the penile tissue healthy. At this point in time You should be getting some level of nocturnal erection or movement. It starts to happen in the first few months as surgical swelling subsides and things heal. Injection therapy will definitely help.
I did all of the above and saw improvement for the first 12 months, but was never quite erect enough for intercourse using shots or pills. My friends that underwent RALP all recovered to the point where they needed nothing or a little Viagra. They were younger at surgery however and that makes a difference in outcome.