on the last page it says the end

I hope it means its the end of the chapter or vol 1 and not the story.

It is the end of the manga. Here is what the scanlation group wrote on their site: For our second release today, we have the final two chapters of Seito Kaichou desu ga Josou Hajimemashita, chapters 17 and 18. The end may seem kind of sudden, but it looks like this series was planned to only last for one volume, which is set to be released next month. After the volume is released, we'll recompile the chapters and include any additional content to complete the series.

ouch. thank you