Yes. Chewing the gum too quickly and too much. Chewing quickly leads to a more rapid release of the nicotine but also creates more saliva. That dilutes the nicotine and makes it more likely you will swallow it. The nicotine in the gum is absorbed best when the gum is resting on the skin of the cheek (called the buccal mucosa). Nicotine is absorbed poorly from the stomach compared to the cheek. Worse, when nicotine is swallowed, it can lead to hiccups, gas, and nausea.
Chewing the gum too quickly may cause a burning sensation. The same is true for lightheadedness, hiccups, gas, nausea, or too much saliva. Begin gently.
Lastly, eating or drinking within 15 minutes of starting or finishing a piece of gum could lessen its effect.
Try not to swallow for a minute or so when you start to release the nicotine. Allow it to be absorbed where it is intended to be absorbed. The first few days are key.