You don't need to be mad studying right now. Just do all your homework and make sure your notes are good, maybe read around the subject a little bit. Chill until after Christmas/mocks, you don't need to be revising until then (though I didn't start until April, but I do not advise this at all - makes it worse come June!). Try to get revision materials for that term done in the half term holiday that follows it, as it wastes time later in the year.
All I can say is I am so glad to be done with A-Levels. Got into uni, so the hard work was certainly worth it, but my god does it kill you on the inside at times.