Pharmacy 4 Less Questions & Answers

I visited my doctor for a severe bout of hay fever. He told me to buy an anti histamine nasel spray. I went to pharmacy4less at burwood nsw
I purchased the azep nose spray.
As soon as I paid for it I went outside to give myself a spray. Because it states on the bottle that “rapid action works within 15 minutes” I waited and waited and it still didn’t work! I was charged for a 20 ml bottle which was over $33. Instead the assistant should have asked me what size do I want.
My nose is running profusely as I write this
I again read the insert and it states it has to be used within 6 months!! I’m an eighty one year old disabled and suffering from parkinson’s decease. I just cannot afford to buy something that doesn’t work.
Can I get a refund or credit voucher for it?