Thank you Sofie for appreciating this class. It is the first Reformer class I filmed for Pilates Anytime in 2012!  Perhaps the dizziness you experience indicates that the motion of cervical lateral flexion and rotation is activating a response of your vestibular system. Dizziness may result when the nervous system is not able to integrate movement of the head and eyes away from upright midline. There are a number of other explanations of dizziness.  If you notice other experiences of dizziness it would be prudent to consult a clinical professional who can work with you to generate an explanation and appropriate treatment.  

Thank you Sofie for this good news update. Perhaps as your thoracic rotation becomes more available less cervical rotation is required. This may decrease the stress on your vestibular system (?).