Can I get JSA if I'm sacked?

I rang in sick 6 hours before my shift with a migraine. I physically can't go into work but they said I have to come in and they'll send me home if I'm really sick. I said if there is an issue with me being ill I can provide medical proof. (I was diagnosed with migraine and I also have medication). I'm worried they will fire me but I'm putting my foot down on this. If I was to be fired for this absence would I be able to get any kind of benefits?