I have to know!!!

When can I start testing if my cycle started the 19th of October and due the 16th of November..(With a 33% chance of pregnancy on the 1st of November) Or should I not take one since I am over weight and wouldn't want to be disappointed.??๐Ÿ˜ข๐Ÿ˜ข๐Ÿ˜ซ๐Ÿ˜ฉ