I bought a house with a small tree growing in the middle of backyard 1.5 years ago. The plan/tree identification app determined that it is a cherry plum tree.

The tree didn't look healthy back then so I decided to create a small circle tree bed with mulch around the tree trunk. I also used a fertilizer once.

The issue is that within past 1.5 years the tree didn't grow much (didn't develop new branches), however, every spring it blossoms. Also, the direction of the main branch is weird and looks like two other branches were cut from the main trunk, I think, by previous house owner a few years ago. Also, the trunk doesn't look healthy and is covered with some weird fungus-like thing.

Does anyone know what's going on with this tree and if there is anything I can do in order to save it? I read somewhere that ferilization + pruning might help. Also, will it be possible to make this branch go in upright direction?