I have discomfort in my lower right side for 4 days.no fever or problems going to the toilet.i pulled a heavy washing on my line to tie it up. muscle?

Seems likely: Your diagnosis seems likely. Treatment would include anti-inflammatory or pain reliever if no allergy or other reason not to take. Moist heat to the area for 20 or 30 minutes several times a day can also be helpful. If no improvement in the next 5 to 7 days, worsening of symptoms, please see your doctor. Hope this was helpful. Best of luck.