It’s very possible that you could have a calling to be a religious sister, but it’s not something that can be determined right away. I’ve been discerning for over 2 years now and I see myself continuing on a few years because I’ve been asked to by the community I am discerning with. I had a friend that discerned almost 9 years before she entered the community she is currently with as a postulant.
It would be very rare for God to just come out and call someone to religious life (although it is possible; nothing is impossible for God). Normally, it takes incessant prodding in the heart and great desires to do something radical for Jesus. I would recommend a spiritual director to help you discern what you are feeling and check out if these feelings are real or just a product of loneliness or something else.
Also, I would recommend that you contact the religious order you are interested in and start building up a relationship. Going on “Come and See” retreats and talking to the vocations director is very helpful. Discerning is much like dating. You wouldn’t date someone once or a handful of times and then marry them. This is a life-changing event. A very beautiful one.
Read up on the lives of the saints–especially St. Paul (my favorite saint, in fact). Read the Gospels. If you are going to live them, you should know them.

It is also helpful to pray the Liturgy of the Hours every day. You can find a free website here:
universalis.com/
Also, continue spending time in front of the Blessed Sacrament.
One of the priests of the religious order I am discerning with (there are male and female members) recommended that I pray three Hail Marys each day for the purpose of consecrating yourself to the Blessed Virgin Mary and she will lead you to your vocation. Praying the rosary every day can do this too. She will obtain for you many graces.
I’ll be praying for you. God bless.
