Hi, im new at growing and so far my plant has been growing about 2 weeks.. Ive noticed my stem has stretched but i got that fixed.. But My problem is my stem is very very weak and long and skinny but i dont noe how to fix it. They are about 3 inches long.. I have a heater fan blowing on them because i cannot get a regular fan since its winter, and i dont have a humidifier. Ive also tried shaking the stem alittle so it can get some resistance but its still very weak, HELP