Knot in Penis: Cancer?

[danielkatzenberger]

Hello,

Because I am in China for work right now I can't see a doctor until December this year.
That's why I am asking you for a rough estimate of my problem.

I have had a blueish lump right under the glans of my penis for some time now. When not erect it visible but not very conspicuous. When erect though, it is becomes pretty obious and grows. It doesn't cause me pain but there is some pressure to be felt now and then.
Right now I am concerned that I might have some form of penile cancer. These thought make it impossible to focus and think about anything. I took a picture, maybe you can gibe me a rough estimate of what it could be: https://unsee.cc/tesudoza/
I know you can't give a diagnosis and I have already made an appoint with my specialist back home for December.
I am 27 and have no other health issues.
Thank you so much.

Regards
Daniel