You might have been affected by an infection with a virus that has in turn caused a blood infection which in turn may cause joint pains in your legs. Antibiotics can disrupt the equilibrium of our body's good bacteria, causing joint pain. For relief of the joint pains, you can try gently exercising, using heat or ice treatment, and taking a break. Stay well-hydrated and eat fresh and good foods to provide adequate support to your body during the healing process.