Scared to be a mom

My whole life I couldn’t wait to be pregnant and become a mother. For years I begged my husband for a baby. Now that I finally have my wish I’m terrified. Will I be a good mom? What if I’m too sick or too tired and baby is pestering? Sounds selfish but it’s true. Please tell me this will change when baby is born. Are first time mom jitters normal or am I being an awful person right now? I can’t even tell my husband