help feel like im dying

I suffer really bad anxiety ive just given birth 10 days ago,i am breastfeeding and i have got some pain in my chest/breast,i get worried about every ache and pain and i always think the worst,like i am going to die,and its so horrible i dont want to die,it really scares me,i dont like to talk about it either,even though im sat down i feel dizzy quite alot,i am on meds and seeing a cbt but its really hard for me