In answer to your question - yes herbalism is profitable.

You wont start making decent money until you are able to farm the upper herbs like Terocones, Netherbloom, and Nightmare Vine.

All 3 of those go for a nice price.  You just need to keep tabs on your AH to see what herbs go for.  On your server, there may be other herbs that sell for a high price (i.e. fel lotus and mana thistle, however, they are harder to farm on a regular basis)  But generally, those 3 alone will make some decent gold and are relatively easy to get.  So hang in there and get your skill maxed out =)