You can say "something happened to my phone". That tells your listener that the thing that happened, happened in the past. Your listener doesn't know whether there is still a problem. So you'd have to add more information: "something happened to my phone and now I can receive calls but not call anyone".
Or, "something has happened to my phone". Now we don't know how long ago it happened, but we're pretty sure that the problem still exists. "Something is wrong with..." means almost the same thing, but here we know for sure that the problem exists now. [You had the right idea. Your only problem was that it isn't good grammar to use "is" with "happened", though everyone would understand what you mean. To be grammatical, you have to use "has" for that construction.]
Or, "something is happening to my phone". With present-progressive, we know that the problem is in the process of changing the phone in some way. The phone might not be unserviceable yet, but whatever is happening will probably have an unwanted result.
@ColleenV
in it and I will try to help.