I'd take the 3.5 months worth of equity just in case and start looking for another job.
(Oh, and next time do your expenses and take a sustainable salary! Early-stage employee doesn't equal martyr.)
OP, listen to kls...now that you've seen how this can go you will really be a lot stronger when you negotiate your next job. There's different kinds of options available too, but unless you ask about which kind you get, you'll just be given the default (i.e. cheaper for the company).
Anyway, the right answer here is to work for someone who doesn't pull crap like this. And if the OP was competent at his job, I would hope the other employees have seen what happened and are properly aware of their employer's shady ethics. In any regard, this is just bad business and likely killed morale to some degree.