Engaged, getting married soon.. Help

I am engaged and we're getting married in January 2015. Our wedding will probably have 300+ people present... And to be honest this is never what I wanted. I wanted a smaller wedding that was done quickly. I don't like long engagements and thinking about how many people will be at our wedding literally makes me sick. I have anxiety and suffer from panic attacks and this is freaking me out. I just want to be married, I don't want a large wedding that is costing me a ton (which it is).
Does anyone think it would be crazy to just have a nice small civil ceremony and then have a "ceremony" or reception when we plan to get married now to appease everyone? Am I insane? Please give feedback, and be kind.