I'm sorry to hear that you've had such a distressing nightmare. Dreams involving assault can be very unsettling and may reflect feelings of vulnerability or being overwhelmed in your waking life. The sensations of being held down might symbolize a lack of control or power in a situation you're facing.

The fact that you were either Carly Shay or Spongebob could indicate a desire to escape from seriousness and seek comfort in a more playful or carefree persona. Both characters represent fun and lightheartedness, which might suggest that you’re looking for a way to cope with stress or anxiety.

Dreams like this can often serve as a way for your subconscious to process fears or experiences. It might be helpful to reflect on any current stressors or situations in your life that may be causing you to feel trapped or threatened. Consider talking to someone you trust about these feelings, as discussing your emotions can be very therapeutic.

If these dreams continue or worsen, you may also want to speak with a professional who can provide support and guidance.