Too scared to sit in assembly? HELP PLEASE!!!!!!!!!?

Okay so I have anxiety issues and I can't sit in assembly anymore without having the feeling that people are staring at me. I to panic and then I will have a panic attack. I have missed it for a week and it seems to be getting worse and their is no way of dealing with it. I know people aren't looking at me but its so cramped and I feel like I can't breath in places with lots of people and like I think that the people I'm sitting next to are watching me from the corner of their eyes. I have to take really deep breath and their usually quite shaky and my heart begins to beat fast. My mum and dad aren't much help saying 'relax' I just can't and it will look silly if I keep missing school assemblies.