Yes, you should speak with an employment law attorney to see what your rights are. You need to be aware that disability is not the same thing as protected leave (e.g. leave under the Family and Medical Leave Act). Disability is a way of receiving some payment or compensation when being unable to work. It does not necessarily entitle you to be away from work without any consequence, such as the way FMLA allows you to take up to 12 weeks (assuming both you and your employer meet the criteria for eligibility) away from work. Thus, the fact that you received disability while unable to work does not necessarily mean that the employer did anything wrong in terminating, then rehiring you. That said, it is worth consulting with an employment attorney who can evaluate your situation in detail.