I too suffer badly with anxiety - I think it's part and parcel of the whole thing, unfortunately, as is worrying that something serious is wrong. I've just gone through six weeks of hell doing this!
I recommend asking your GP to change your medication. There are lots of anti-anxiety meds and different strengths so, like HRT, it's just a matter of finding one that works for you. Bear in mind, though, that they all make the anxiety worse before they make it better - I've no idea why this happens and it seems like a cruel irony!