Did they do a CT scan of your head while you were in the hospital? Most hospitals use a long lasting numbing medication and you may feel weird as it wears of... Kind of like when your foot falls asleep.. that tingling feeling. Any time you have head trauma you should talk to your doctor about concerns. That being said, given the trauma you may have a little nerve damage that will heal with time. If you are vomiting, nauseous, or feel worse, you will need to return to the ER.
Head wounds bleed a lot, hence your stitches. It is normal to have discomfort and numbness. Icing the area will help reduce pain and swelling. Follow the precautions given to your parents when you were discharged from the ER. Keep your wound clean and dry, and it will heal soon. Take care!