Suggest Treatment For Neck And Shoulder Pain

Hi, This is Trisha and I am 27 yrs old. I am experiencing neck, shoulder and arm pain since last 2 weeks. The pain aggravates while I am walking or have some pressure on my shoulder, like carrying a bag. My neck also becomes very stiff in the morning. When I am at rest all day at home, I do not experience much problem. This is related to any sort of activity. Please suggest. Thanks!