Levonorgestrel
"Hello. I have taken the UK version of this pill Levonelle once. Like pretty much everyone here, I found myself searching for reassurance that everything was going to be ok. I was desperate for it to work after the condom split for the first time ever in my life and I'm 32. I didn't really have any side effects and my period, thankfully, arrived 2 days early. There is no point in me telling you not to worry as I know I still did when everyone around me was saying not to. However, what I will say is that you are not alone. Thousands of others are going through the same thing and strangely I found that comforting. Good luck if you are still waiting for Mrs Flow. Hope you have as good an outcome as I did, if that's what you want, anyway."