title: C# Timer Interval doesn't work
body: <p>As written in the title, something in the Timer Interval seems to be off. The timer should take the time from a "DateTimePicker", convert it to seconds &amp; change the Interval to the time set on the DateTimePicker. Afterwards it should post a tweet on twitter, though it doesn't work. It just keeps spamming posts over and over.</p>
  
  <pre><code>            private void IntervalChoose_ValueChanged(object sender, EventArgs e) //DateTimePicker
      {
          postInterval.Interval = (IntervalChoose.Value.Hour * 3600) + (IntervalChoose.Value.Minute * 60) + IntervalChoose.Value.Second;
          saveTimerInterval = postInterval.Interval; //saveTimerInterval is set 0 at the beginning
          MessageBox.Show("Current Interval in Seconds: " + postInterval.Interval.ToString());
      }
  
      private void button1_Click(object sender, EventArgs e)
      {
          if (button1.Text == "Start Bot") //Starts program (works)
          {
              IntervalChoose.Enabled = false;
              MessageBox.Show(saveTimerInterval.ToString());
              postInterval.Interval = saveTimerInterval; //Sets the interval (once again, safecall)
              postInterval.Start(); //starts posting.
              button1.Text = "Stop Bot";
          }
      private void postInterval_Tick(object sender, EventArgs e)
      {
          var service = new TwitterService("", "", "", ""); //Auth Keys
          var twitterStatus = service.SendTweet(new SendTweetOptions() { Status = "Hi" + counter });
          if (twitterStatus != null)
          {
              MessageBox.Show("Your Message:\n\n\"" + "Hi" + counter + "\"\n\n has been successfully tweeted.", "Success!", MessageBoxButtons.OK);
              counter++;
  
          }
          else
          {
              //MessageBox.Show("An Error occured while the Bot was running. Please Contact the Developer.", "Error!", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
          }
      label2.Text = "Next Post in:\n" + (postInterval.Interval / 3600) + " Hour(s) " + ((postInterval.Interval / 3600) / 60) + " Minute(s) " + (((postInterval.Interval / 3600) / 60) / 60) + " Second(s)";
      }
  </code></pre>
  
  <p>Result:</p>
  
  <p><img src="https://puu.sh/qtUSe/d2a98f2dd8.png" alt="Picture 1">
  <img src="https://puu.sh/qtUZB/67bd826d79.jpg" alt="Picture 2"></p>
  
  <p>As seen in the Pictures, the label won't refresh, nor the new set time is being used. It just randomly posted text in a random time.
  Thanks in advance for the help.</p>