R.M.
I can't really help with the tantrums part, because I am still working on this myself. Isn't 2 fun?! Mine talks a lot and is still a little monster lately.
I did want to reassure you on the speech thing though.
I think that teaching 2 languages does delay a little bit. NOT to say you shouldn't do that, it just takes them a little longer to learn language in both and learn to process it and say what he wants. Once he does all that, he will be at an advantage knowing two languages, but in the meantime I have read that it can make them talk a little later.
Boys DO talk later on average, and 2 is still pretty young to be worrying about this.
And last, signing with baby can cause language delays also. Again, not to say you shouldn't do it. But it is the same as the 2 language thing- he is having to learn more than most kids. In your son's case- 2 or 3 words to my son's 1 word.
Tantrums can be worse due to not being able to express themselves. They get frustrated even more than another two year old, and they aren't known for their patience and self control anyway- lol.
You don't say how much he is talking, but if you are really concerned, you can go back to your pediatrician and tell the doctor you want to have him evaluated and possibly get early intervention for speech delay. I'm sure one of the moms on here that has done this will be able to tell you the process for this. I think some doctors like to wait until 2 1/2, but yours might go ahead and refer you now. I'd start making a list of all words that he does say, and include both languages plus the signs he knows. The doctor will want an accurate idea of his development, and so will a speech therapist if you do end up doing that. My nephew has a slight delay and at 2, my sister's pediatrician told her to start making a list, and she had a certain number of words he should have been able to say by 2 1/2.
I hope you get some good terrible two's tricks. Try not to worry too much, and just remember to take a deep breath (or 12) when he is acting up. I do a LOT of deep breathing these days :) Patience isn't really my strong suit either.