diff --git a/src/TweetFetcher.php b/src/TweetFetcher.php
index ac84d78..1c4b211 100644
--- a/src/TweetFetcher.php
+++ b/src/TweetFetcher.php
@@ -54,7 +54,7 @@ class TweetFetcher implements TweetFetcherInterface {
 
     // Ensure that we have an actual API exchange instance.
     if (empty($this->twitter)) {
-      throw new \UnexpectedValueException('Twitter API exchange has not been initialized; credentials may not have been set yet');
+      throw new \UnexpectedValueException('Twitter API exchange has not been initialized; credentials may not have been set yet.');
     }
 
     // Query Twitter's API.
@@ -64,7 +64,7 @@ class TweetFetcher implements TweetFetcherInterface {
       ->performRequest();
 
     if (empty($response)) {
-      throw new \Exception('Could not retrieve tweet ' . $id);
+      throw new \Exception("Could not retrieve tweet $id.");
     }
     // Handle errors as per https://dev.twitter.com/overview/api/response-codes.
     if (!empty($response['errors'])) {