It's completely normal to feel stuck and overwhelmed during the PhD journey, especially when facing unexpected challenges like having to redevelop your research proposal. Remember that setbacks and revisions are part of the research process.

To move forward, I suggest taking the following steps:

1. Communicate with your supervisors: Share your concerns and the challenges you've encountered. They are there to support you and can provide guidance and suggestions for overcoming obstacles.

2. Reflect on your first study: Analyze the results and identify the key findings and implications. Consider how these findings can shape the direction of your next studies and inform the updated proposal.

3. Brainstorm and generate new ideas: Explore different research questions, methodologies, or angles that align with your previous work and interests. Engage in discussions with peers, attend seminars or conferences, and seek inspiration from related literature.

4. Seek input from others: Collaborate with colleagues or reach out to experienced researchers in your field for their insights and feedback. Their perspectives can help you refine your ideas and provide fresh perspectives.

5. Break down the tasks: Create a clear timeline and set achievable goals for each step of the process, including updating the proposal and developing detailed plans for the next study. Breaking it down into smaller tasks can make it more manageable and less overwhelming.