My left sidebar

could be caused by one of the validation errors (untested)
http://validator.w3.org/check?uri=http%3A%2F%2Fbalkan-tourism.com%2F&charset=%28detect+automatically%29&doctype=Inline&group=0

http://codex.ww.wp.xz.cn/Validating_a_Website

what edits did you make to add the second sidebar to Twenty Thirteen?

[topic closed as duplicate of http://ww.wp.xz.cn/support/topic/left-and-right-sidebar-widget?replies=9 – please continue with your original topic]