Hello, i'm a begginer gardener and I bought this lemon tree 3 months back. The tree had flowers blooming and was full of leaves. Once I took it home, the leaves began to drop and the flowers began to dry and fall as well. After about one month of that happening it stopped and my lemon tree only had a few leaves left. It sprouted some new leaves and I thought it was getting better. About two weeks ago, the lemon started loosing leaves again. Now I am left with two leaves on the tree and the rest are shriveled. Most of the branches are brown and look dead. I water the tree once a week and have not put any additional fertilizer since it was bought. Im starting to think the tree has some kind of disease. Please help me with this issue. I dont want my tree dying. Thank you!