I got checked for prostate cancer?

DRE is just the "finger wave" test for an enlarged prostate which is unlikely at your age. 

I think what is going on is that you have a diverticula, or a breach in the wall of the urethra which has formed a space that fills with urine and creates this ball under your penis when you urinate. This is a complication of some urethra reconstruction surgeries to correct hypospadias. A related issue is stricturing, which will make peeing difficult and increase the amount of pressure required to empty the bladder. Both of these complications are related to the anastomosis, or joining between the original urethra and the constructed repair

Bladder cancer? Unlikely unless you have been seeing blood in the urine, and carcinoma of the bladder would not cause the ballooning when urinating. 

Bottom line, it sounds like you may eventually have to go in for revision urethroplasty to correct this. Just a word of advice...find a surgeon that specializes in adult hypospadias revision and repair. This is a different ball game than pediatric surgery.

you don't have or ever had prostate cancer

get a second opinion / urologist

I dunno what's up with you. You've discussed "major reconstructive surgery of the  urethra to correct hypospadias"  I dunno if you've had that done (which would explain your urine "ball")  or if you've got some other urinary  problem.   If YOU have had that surgery, go back to the doc who did that for best advice.  (I also wonder if you've just discovered this condition on line and now have a fixation about it.)     Cancer at 26? It happens, but prostate cancer is REALLY rare at your age, and the primary cause of bladder cancer is years of smoking. At 26, you'd have to smoke A LOT to get bladder cancer. And unless others in your family have had bladder cancer in their 20s or 30s,  I'd say that's not likely for you.   As a man, I can tell you what dix are supposed to do, and a "ball" of piss is NOT supposed to happen. 

If you have this "little ball" (bubble/pocket) that only forms as you urinate and dissipates when you're done, you should consider having that corrected... this "flaw/defect" may be what's causing your restricted urine flow.

go back and say the lump only comes when u urinate. Or go to another dr. fro 2nd opinion and other etsts eg MRI