Liliz, your avocado doesn't look too bad. You may have noticed a little less healthier older leaves as the new leaves push out. The older leaves will eventually dry up and die off to make way for the new leaves to grow. I notice a little dry tip on the new growth .. not sure if that was the case as it was a little hard to see clearly. If you keep the plant hydrated, I think it should be ok. As far as I'm concerned, you have a nice looking plant there and it should do well. As to the cold, I think young plants tend to be a little more sensitive than the older ones. If in doubt, just get it indoors if you think it's too cold outside. This time of the year, it should be rather warm for all plants ... so what's your planting zone?