Today is July 23rd and exactly 1 month ago. That same day I had heavy bleeding and the doctors had told me that I was going to need to have a D&C. They told me to wait 4 weeks to start having sex. I only waited 2 full weeks. On the third week I started again and when I had sex again, me and my boyfriend didn't use protection. Is it possible for me to be pregnant again?

Yes it's possible.

It's possible that you are pregnant. It's also possible that you contracted an infection due to not waiting until the required time to resume sexual activity.

There are Reasons we tell you not to have sex within a certain time limit.