Anxious about change...

Just found out we are pregnant with #3. I have a boy (5) and girl (3). We were so excited to try for more, felt romantic and fun to think of all of us experiencing this miracle together. Now with nausea and aches at an extreme, people sick left and right and the reality of all things that will change approaching... (room rearrangements, family negativity, car re-size, etc)... added to our already busy schedule wearing us down...I wonder did we make a mistake ? Everything was just getting easy. I feel so lost. Advice please? (5 wks plus 4 today). Please do not be offended by my post. I understand and am thankful for what I have and will receive. Just nervous to change what is good and seeking support from other moms...