It is common for pregnancy symptoms, such as weakness, to fluctuate or disappear altogether during the first trimester. Every woman's experience is different, and not feeling weak at 4 weeks pregnant is considered normal. However, if you have any other concerning symptoms or if you are unsure about your well-being, it is always best to consult with your healthcare provider for personalized advice and reassurance. They can evaluate your specific situation and provide guidance based on your individual needs. Remember that every pregnancy is unique, so what may be normal for one person may not be the same for another. Trust your instincts and seek professional medical advice whenever necessary.