Medication and reactions

I have been on venlafaxine for a while (I'm on 300mg a day) I was on the normal pills that you take twice a day but I was getting bad side effects since my dose was increased from 150mg to 300mg about 6 weeks ago so my doc switched me on to slow release caps 3 days ago the side effects do seem to be calming down a bit but I woke up yesterday my Tongue and throat where swollen and still are today I am having difficulty swallowing and struggling to breath I can't get in to the docs untill it reopens on Monday and I can't stop taking the pills because of really bad withdrawral symptoms
I am panicking now thought as I think I might have some kind of allergic reaction but is it possible as it is the same medication just a different form

Thanks in advance for any help

Stop taking the pills immediately. You are allergic

I know the withdrawals are a nightmare but this pill could kill you.

Try to take something else for your anxiety or depression like xanex vicodin or marijuana until you can get a new prescription.