Sounds like Halasana.
There are several things to mention to you here as you are just beginning your practice.
In Purna Yoga, the yoga in which I am trained, practice, and teach, we hold the concept of safety as THE top priority. And at the same time we are working diligently to bring the marvelous effects of the poses into the student's body. It can be a very challenging rope to walk:-)
Halasana is not a pose that should be used by beginning students. Simply put, the student just coming to the practice does not have enough asana (poses) yet in their body, enough action, enough understanding, enough opening, enough stability to do such a pose with integrity.
When a pose is done without integrity it is merely gymnastics or contortionism. Those are not bad things. They are fine. But they are not yoga. Yoga must have integrity as a core principle.
Halasana, much like Sarvanggasana (shoulder stand) should be done using folded blankets or a foam pad supporting the shoulders and the 7th cervical vertebra in order to preserve the cervical curve (neck). This is something we have learned over time in yoga and is one of the ways we have to grow yoga so we can keep our students healthy and reduce rather than facilitate injuries.
Therefore even when the student is beyond the beginning level the propping is still used. Translation: even intermediate students do the pose this way in an asana practice that emphasizes safety.
Bear in mind that I am not a medical practitioner and therefore you should not misinterpret my feedback as medical advice or consultation. That having been said, you will likely be "ok" but David makes a strong point which I will alter a bit to suit my perspective - please see the health care practitioner of your choosing if you are at all worried. Worry is NOT helpful:-)
That particular pose, when done flat on the floor as I suspect you did in the gym you are attending (assumptive, I know) can place strain and pressure on the neck. So you may simply feel wonky from that and it may easily pass in a few days. Please consider not doing that pose and/or not at all even thinking about it until you are un-wonky.
If you are interested in having a lifelong yoga practice please weigh the value of a well trained teacher and then act accordingly based on that process.