Your “I need to think about it” is why you have the problem you have.
Here's the problem:
You need to make a decision, but you're not sure what to do.
You don't want to make the wrong choice, so you stall. You procrastinate. You get distracted by other things. You do anything but make the decision.
But guess what? The longer you wait, the worse it gets.
When you find yourself thinking about what could happen rather than moving forward, it means that you are afraid of the outcome. That fear prevents you from taking action and making decisions in the moment, which is why it becomes harder for you to make decisions and take action as time goes on.
You can't just sit around and hope something will happen to solve your problems for you. Often, it won't. So what can you do about it?
Ask yourself: What's holding me back from making a decision?