Panicky, Sleep Deprived, Breathless, Anxious, Smoker
Thanks for posting your query.
There could be many reasons for this.
The commonest reasons includes
1. As pointed out by you "anxiety".
2. Digestive problems.
3. Some respiratory problems.
As observed by you, this happens when you are under stress or anxiety, this reason makes more sense. At time of stress when you are feeling low, you tend to have problems like this. At this moment any minor aliment seems big.
As you are smoker, gastric problems are frequent and smoking can lead to increased secretion of acid in the stomach, and at times leads to development of this kind of symptoms due to regurgitation of food back in to food pipe specially after a large and fatty meal.
The best thing for you is to visit your Take light diet, do regular exercise and have proper sleep.
Try to fine out the reason which makes you anxious. Avoid having soft drinks and coffee etc, which can lead to increase problems due to stimulation of brain.
I hope this helps you and makes you understand things properly.
If you have any follow up queries, I will be glad to answer them.
Regards
Dr.Pragnesh