Everytine I try to play my movie, the video plays back in slow motion, it worked fine before, I have windows 8
These questions below may be for a different product... but the information you need to supply is the same, for the products you use
-Information FAQ http://forums.adobe.com/message/4200840
Also, exactly what are you editing?
Importing Video http://forums.adobe.com/thread/1065281
-and project settings http://forums.adobe.com/thread/1112086
As John indicates, this is most likely related to your source video. Version 7 was not optimized for high-definition AVCHD video and it really is out of its league with video from pocket camcorders and mobile phones.
Where is your video coming from and what format and resolution is it?
When you started your Premiere Elements project, which project settings did you select? (You can see your project settings under the Edit menu.)