The best thing you can do is go into the Dr and get your labs done. Something is off here or you would be making gains. Without knowing more details about your program, I'd really only be guessing. You have 3 different variables that could be causing you problems. This is why i suggest that new users use test only for a first cycle and add no more than 1 new compound per cycle. That way, you know how each drug effects your. You may have an issue going on with high or low estrogen or proges from the deca. Everyone responds differently to deca. It shuts me down bad and i need to run at least 200mg more test than deca. This could be a cause for strength loss. Its only a theory though. I experienced that once before, some years back. With your level of expereince, I would just remove the deca from this cycle and save it for the next cycle. At this point, it's only going to complicate things and you really aren't going to make better gains than if you run 500mg of test alone. If your sex drive is up, something is working. It would be nice to see the actual numbers though.

Its also hard to say exactly whats going on without knowing more about your program and what your diet looks like. If your test levels come back high, as they should, then we know its not the gear but something to do with you. Everyone tells me they eat plenty but until i see their diet, I've learned to remain skeptical. For your size, "Plenty" would be somewhere arond 400g protein, plus 300 or more carbs. This could be part of the issue. Also, Im going to assume that you are taking 30mg of OT total, split into 3 doses, not taking 30mg, 3 times a day, totalling 90mg. 30mg is a low dose of a steroid that isnt really for much in the way of mass. 

Also be aware that outside of the water retention that comes with test, usually starting around wk 2-4, it isnt really going to give you much effect for about 3-4 wks, By the end of 4 wks, I'd expect to see some mass starting up from the test.