diff --git a/twitfix.py b/twitfix.py
index 7607329..cd27e3d 100644
--- a/twitfix.py
+++ b/twitfix.py
@@ -112,9 +112,9 @@ def twitfix(sub_path):
             twitter_url = "https://twitter.com/" + sub_path
         else:
             # URL normalization messes up the URL, so we have to fix it
-            if sub_path.startswith("https:/"):
+            if sub_path.startswith("https:/") and not sub_path.startswith("https://"):
                 twitter_url = sub_path.replace("https:/", "https://", 1)
-            elif sub_path.startswith("http:/"):
+            elif sub_path.startswith("http:/") and not sub_path.startswith("http://"):
                 twitter_url = sub_path.replace("http:/", "http://", 1)
 
         if isValidUserAgent(user_agent):