I feel compelled to eat soap and wax objects - could I have ocd?

Maybe. The problem you have is called pica. Depending on what compels you to eat the objects you mention you may or may not have pica. It is usually related to pregnancy or psychosis but some individuals have been known to do it under stress. If it is truly a stress-related compulsion that bothers you than OCD would best define it. Whatever the cause it can lead to significant GI problems so seek help.
Yes. Saying you are compelled is enough to classify this eating disorder as a "spectrum" disorder in my opinion. Spectrum disorders are those that overlap traditional ocd. When children do this it generally is called pica. Pica can occur in psychotic or demented individuals as well. Get professional help since this kind of behavior can lead to serious physical illness.
PICA. PICA-requires immedate psychiatric intervention. The bigger issue is how long has this been going on? and is there any underlying psychopathology.