I went to ER twice last week desperate for help and relief. Got no help at all. Feeling quite helpless. Day 12 of migraine. I need something to break it

My doctor refuses to prescribe any opiate based medication. They are believed to make migraines worse or cause rebound migraine. I live in the U.K. And we can only get this on prescription. You can get a cocodamol 8/500mg mix of 8mg codeine and 500mg paracetamol OTC.
I've used dihydrocodeine and it has helped as well prescribed 30/500 cocodamol.
The times I've been to hospital for emergency help with debilitating migraine they've administered quite a healthy dose of morphine. Injected straight into the ditch of your arm. It helps distract you from panic and the overwhelming pain, but the overlying pain is still there. Hell

My sister lived in Canada several yrs back and she could buy it over the counter their but I've never heard of it over the counter in the US.

The only reason I ask was because in the meds on this website it states you can get them in some states over the counter.

It's stated under the treatments.