Are migraines after a serious car accident normal?!

They can be normal to get but are abnormal in themselves. First your head had to whip to hit hard to put you out like that. When your head is whipping like that and then makes a sudden stop it's your neck muscles that get the brunt of the force and go into pain and, as one therapist said, locks the pain inside of them to give you what is now a migraine. The neck muscles go to the top of your head where they connect to muscles going around the brain. When the neck muscles get tight they pull on the head muscles and when they go into pain you have your migraine. Here's how your eyes get involved into the pain, the nerves for your eyes go to the back of your head passing right next to the neck muscles. When the neck muscles are tight they can press into the nerves for your eyes to cause pains on the back of your eyes. More pressure will cause the pupils to dilate to make things go blurry. As the back and neck muscles share muscles in the lower neck/upper back, both places can be tight and feeding into this and if you had internal issues you may have some tight muscles in this area as well so freeing up these muscles along with your neck muscles will get rid of the pain. As this has been going on for so long you may have to repeat this 3 or 4 times a day for a week to get all your muscles freed up and to keep them freed up to be rid of the pain. The back muscles you can get by doing once a day. Here's how to free up your back and neck muscles to get rid of the pains and the migraines:
Neck
Put your hands alongside your head so your thumbs are on the front of the muscle under your ear and your fingers are on the back of the muscle behind your neck. Squeeze your thumb and fingers together and hold. Relax your body. When your fingers and thumb touch, about one minute, slowly lower your head as far as you can, release the pressure but hold your neck lowered for another 30 seconds.
With your neck in the lowered position, replace your thumbs in under the ears and your fingers behind your head but right next to your skull this time. Press your fingers and thumbs together again and hold. Relax your body while waiting. When the muscles have all released, slowly lift your head until it’s level again, release the pressure but hold your head like that for another 30 seconds.
Back:
(do from a sitting position)
Place your left hand on your left leg next to your body. Place your right hand over your left shoulder, fingers over the back and the palm in the front and firmly pull down on them and hold. After 30 seconds slowly lower your body forward and to the outside of your left leg, keeping your left arm fairly straight as you do. When you reach your lap remain there for another 10 seconds, release the pressure but rest there for another 30 seconds. Then reverse your hand positions and do your right side. For both- for best results relax your body first by taking a deep breath and exhaling then remain this relaxed.

I'm no doctor, but your doctor IS. haha obviously...
Anyway, if he says it's ok it's ok! It's probably just a side effect sort of thing from severe head trauma. Yep...