Hi Curiouscaseyx. Welcome to the forum.

I'm not a doctor and I have no medical qualifications.

As a proud owner of a similar set of equipment, I can safely say that most men find their naughty bts sensitive - which is why a kick in the testimonials is so instantly debilitating.

In your position, I'd tell your boyfriend to see the doctor.  There may be a simple organic cause for the increased sensitivity.  It's unlikely to be cancer, but it would be best to get it ruled out.