I dont want to fully alarm you, but ive had this same thing happen with two of my elms. Both times it was after a light pruning after the first flush hardened off. Both elms died as a result. It started at the tips and worked its way down to kill each branch. Heres why i say dont be fully alarmed. It looks like youve caught it early.
What you can immediately do:
1.) watch your watering. Water only by hand with a small spread, being careful not to splash on the leaves or branches. I think my problem was that i was letting the leaves get wet when i watered.
2.) get it out of the rain, if theres any right now.
3.) and this one is most important, buy bonide infuse granular systemic fungicide. You can get it on amazon for 24 bucks. Pay the extra fee to get it in a day. Sprinkle a small dose. About a teaspoon and a half, evenly around the tree.
4.) i wouldnt necessarily suggest usig a copper fungicide, but if the bonide doesnt seem to be working, give it one spray.
5.) if you have normal household hydrogen peroxide, put it in a spray bottle and lightly mist your entire tree, and water it into the soil. Do this today. I found it helped arrest the fungus. But do not let it drip from the leaves down onto lower branches. Mist just enough that it clings to the leaves. The fungus i had, and it looks similar here, was transported by water.
6.) remove infected leaves by finger plucking. If you want to cut you can, but disinfect your tool thoroughly when done.
I hope this helps. Be proactive now. Dont make my mistake. My tree was in bad need of a repot at the time, and i think thats why it was susceptible. If you want, you can tip the pot on an angle to improve drainage and airflow to the roots