Is it backbiting if I complain to my mother than I feel that my brother is making Hasad on me? And if I tell her that I feel he is to nosey and tries to find out what I do too much

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

First of all, you should beware of suspecting your brother because suspicion is the worst of false tales, as the Prophet said: “Beware of suspicion, for suspicion is the worst of false tales.” [Al-Bukhari and Muslim]

If you really know that he is jealous about you and it is not a mere suspicion, then it is permissible for you to complain about him to your mother if you think that she has the ability to stop him from envy or stop him from spying on you if you know that he does so.

There is no backbiting in this complaint, Allah willing, because this is about the person who is oppressed complaining about the injustice inflicted on him by others.

Ibn Hajar al-Haytami said in az-Zawaajir:

“In principle, backbiting is prohibited; and it may be obligatory or allowed in certain cases for a valid Islamic purpose that cannot be achieved otherwise. It is permissible in some cases: the first: when the wronged person complains to someone else whom he thinks that he has the ability to remove or to reduce his injustice…” [End of quote]

Allah knows best.