Help. We're Unfortunate.

So. My boyfriend and I had sex for the first time this past weekend. It was quite the task trying to find out how we had to position ourselves in order to get everything in... But we got It eventually and it was great. 
Well... We wanted to try again today and we literally could not get positioned right to get it in. I don't know what we did differently or what we're doing wrong. 
Please.. Someone tell me we aren't the only ones that have an unfortunate time the first couple times..