You are more than welcome and all the best on the appointment. If anything, in the least, it will hopefully bring some peace of mind, which helps too.
Perhaps they are cysts and that you just never properly felt them before. It is hard to say. I just never hesitate to go back in if there are new symptoms, the symptoms increase or if they persist longer than the doctor said that they would. It's just a easier to me o be safer than sorry. If that makes sense.
A scrotal ultrasound is really the best test to have to look for anything suspicious for testicular cancer. If this is a new symptom, then I wouldn't be hesitant to go back to the doctor to discuss it and see if a follow up ultrasound would be appropriate.