Year-long testis swelling causing pain, what to do?

The possibility of your boyfriend's methamphe­tamine consumption leading to a failed urine­ drug test for you tomorrow is improbable. The like­lihood of drugs entering your system through his e­jaculation during intercourse is minuscule. 

It appears you may be having a condition called frenulum breve, where the skin under the penis head is very narrow. This could cause pain during intercourse. The pain from your previous cut might have made it tighter. It is something that you should discuss with a doctor so that he could guide you through the different options like stretching exercises or to fix this issue through surgery.

Sounds like you may be experiencing premature ejaculation. Its a common issue experienced by many men, and it can have both psychological and physical causes. Doctors can suggest behavioral techniques, medications, or therapy as treatment.

Pain in your lower abdomen and urinary tract, along with difficulty urinating or having a bowel movement, might indicate a blockage. Conditions like kidney stones or an enlarged prostate can cause this. It's crucial to seek medical attention as soon as possible for proper treatment and relief.

Generally after surgery, it's recommended to avoid any activities that can put strain or pressure on the surgical site to allow for proper healing. Engaging in sexual activities including masturbation could potentially impact the healing process, especially in the early stages of recovery. Consult your surgeon who performed the surgery for better guidance.