My husband abandoned me and my son and has just been ordered to start paying child support, can I get alimony also?

Child support is calculated by guideleins imposed by the state.  They are fairly straightforward as to what income in included and if certain incoem is excluded.  If your husband was hiding assets and income so that they were not calculated in to the equation and you were able to prove it then you could go back to court to have the  amount increased.

Also known as post-divorce maintenance, spousal support or spousal maintenance, it is my understanding that in Texas, post divorce spousal maintenance is relatively new and often difficult to obtain. The Texas Family Code generally requires that the marriage be at least 10 years in length, that the spouse seeking the alimony be unemployable due to lack of basic job skills in the marketplace, or otherwise unable to work due to disability or the need to care for a disabled child, and a finding that there are inadequate marital assets that would provide for minimum financial needs of the spouse seeking support. Spousal maintenance is limited to a maximum of three years with some limited exceptions that can extend support, and is also limited in amount.

Seek legal help with all of this.  Good luck.