I am about 10 days before my menstrual period and for the past 4 days I have had a thud feeling in my chest accompanied by a brief shortness of breath, these instances happen 1-2 times per day, usually around 11pm, only one being at 11am, this all lasts about maybe 5-10 seconds. I am experiencing no dizziness or pain. Ive cut back on all caffeine a few days ago to rule it out as the cause of the issue however Its still happenning, It all happens when im sitting on the couch calmly. Ive had issues with anxiety in the past, however these issues never happenned with my anxiety and I am currently under no stress