I feel two behind my right ear. could that be a side affect of acyclovir?

the upper right hand corner of my forhead i get zoster or its shingles. my doctor isnt sure. and ive gottne them since i was 7 im 14 now. and my doctor gave me acyclovir 800 mg capsules 5 times a day. i feel about two in the back of my right ear....what can cause that. i checked the side effects of the pill and the side effects are headaches, diarrea, and stuff. but not what im feeling. what could it be? HELP PLEASE and thanks !!!