Brief Answer:
There can be a temporary numbness,also blood clot and secondary infection

Detailed Answer:
Hey thanks for your faith in the health care Magic
I have gone through your question and I understood your problem.
You have undergone a submandibular gland removal operation. So I would first like you to know its complications. These are as follows.

Blood clot: A blood clot can collect beneath the skin in a small number of patients. This may require a return to the operating theatre.

Wound infection: This is uncommon in the neck but can happen if the submandibular gland was badly infected. Wound infection will require antibiotic treatment. Pus collecting under the skin may need to be drained.

Facial weakness: A branch of an important nerve passes under the chin close to the submandibular gland. It makes the lower lip move and if damaged or bruised during surgery it can lead to a weakness of the lower lip. In most cases this nerve works normally after the surgery but a weakness can occur which is usually temporary.

Numbness of tongue: The nerve which gives sensation and taste to one half of the tongue runs close to the duct of the gland. Rarely, this nerve gets injured leading to numbness of the tongue immediately after the operation. This will usually go, and permanent numbness of the tongue is rare.

Now coming back to your problem you said your neck is abnormal in its look. well by seeing your pics I will say not much to worry about as I couldn't find any gross abnormality in it.Rest is a clinical judgement of your treating doctor

You also are complaining of numbness which as I have explained earlier is temporary most of the times and will vanish over a time.
You also complained of swelling and inability to rotate your neck which for me can be due to blood clots and secondary infection which we need to differentiate clinically.So my advice is dont ignore it and consult with your operating surgeon as soon as possible.
I hope my answer was helpful for you . Thank you.
DR . XXXXXXX HASABE

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