I fell on my knees when I was abt 15 weeks. Didn’t felt anything wrong nor did I went for checkup. 27 weeks now. Sld be ok as long as there’s no bleeding and like afar you mentioned, there’s movement in your stomach which indicates that your baby sld be fine
i recalled tripping & falling too but didnt feel anything untowards so did not consult doctor but do seek doctor's advice if u r worried.
follow yr heart if u are worried seek opinion frm doc..take care