Hello,
Yes cats in heat may exhibit a variety of signs. Some are over affectionate and will rub on their owner and roll on the ground. They will often vocalize a lot more and also flag their tail or flip it back and forth.
Growling at the window may be another sign, although not as common.
I would get her spayed as soon as possible. Cats are induced ovulators, so they will often take a long time to come out of heat or even have repeat cycles very close together. Spaying is often needed to get them to come out of heat.
Hope that helps, let me know if you have any other questions.
Cat Veterinarian
DVM, Emergency Veterinarian; BS (Physiology) Michigan State Univ