too hot, light too far away or improper spectrum, (many times - the window sill light will do this) - these are the general causes of stretch
your seedling needs - air flow -will strengthen the stalk
support - crumple paper around the stem to hold it up…do not wet the paper much as it can rot the stem…only leave about 1 inch of the stem, right under the first flowers
OK thank you I’ll do that
How many inches long is that? Pretty cool really.