Testicular and low abdominal pain

Hi, my son who just turned 12, started to have pain on his left testicle.  He ranged it on 4 to 5, on a scale from 1 to 10, being 10 the strongest.

We went to the doctor and they said it could be varicocele, but it was too early to verify.

Five days after, he experienced pain in his right testicle.  We went to the doctor again - another one, and they asked him some questions, and he said everything was normal, to take and Advil in case the pain persists.

Two days after, my son is experiencing pain in his low abdomen, not sure if it was in the inguilinal area, but he rated it between 5 to 6.

Not sure what to do, if to take him to the doctor again, or think they are just pains normal of the "getting into puberty" phase.

Thanks in advance for your comments, will be really appreciated.

PR

If he was my son,and I've had 3 sons,I would take him back to the doctor,even if it was just for peace of mind. 

you need a new doctor if no ultrasound has been done.