my girlfriend [18F] of 3 months wants to take a break with me [18M]

I dont usually post here, so ill cut it as short as possible:

yesterday my girlfriend [18F] confronted me [18M] and told me that she needs space from the relationship, because after a week of space and her going on holidays, her attitude towards the relationship changed.

it was really noticeable, he texts became drier and drier (and because snapchat was our main communication outlet), the snaps she sent of herself looked sad and moody. I called her out on this very empathetically, after all I am really in love with her and only want her to be happy.

she then spoke about how she has been feeling ‘weird’ about the relationship, how she felt as if she randomly lost attraction and no longer imagines a happy future between us as a couple.

now for the last 2 or so weeks we both have been dealing with our own personal stresses, we both have uni coming up and our family issues don’t make anything better. during this 2 week period I fell into a depressive episode and was getting jealous over small things, and i was also not able to see my girlfriend at all due to us having busy work schedules.

us being busy though had never effected anything. after a long day of work she would come over and we would get stoned, cook the best meal of our life’s, cuddle while watching our favourite show and have great sex.

while she has stated shes not breaking up with me, she is really unsure about the future of the relationship and wants to take a break to work on herself and her problems. I trust this wont lead to any cheating situations since we are both clear on our stance of it, however I just dont know how long this break would last, or if its even possible for her to gain the spark back.

would anyone know how long id have to wait ?