A diet filled with healthy foods can boost your energy by supplying your body with the nutrients it needs. Include plenty of protein in your diet because it can increase your energy. Add lean meat, fish, milk, cheese, nuts, seeds and legumes to your daily diet to increase your intake of protein. Foods high in fiber can also boost your energy because they digest more slowly than foods low in fiber. Whole-wheat bread and pasta, brown rice and fruits and vegetables are good sources of fiber. Eat iron-rich foods as well. An iron deficiency can cause fatigue and sluggishness. Include seafood, beans, tofu, leafy green vegetables and fortified grains in your diet to boost your intake of iron.

Fever periods can be followed by weakness for few days , and you are also taking antibiotics hence it’s usual to have weakness

This generalised weakness and fatigue is normal after any fever episodes. Have nutritious diet, drink more water, get enough sleep.