If you have already had an orgasm without ill effects, you may as well continue
I don't use Viagra or Cialis, so can't comment on those -- but I do know that it can be a period of months before you see any effects.
Re the pump. Yes a cheapie from the adult store will work, but may not last very long. I broke mine after three months -- squeeze bulb split -- clearly not designed to last. However, while it lasts, the pump will be fine for exercise. For constriction, I used office rubber bands, surprisingly effective.
Although a lot more expensive, the medically approved pumps are better. They will last longer, and should have a better method of applying constriction rings. Also, if your surgeon prescribes it, it may be covered by your insurance.