My manager told me that working overtime is just part of the job and that I'm expected to work overtime.
This is wrong, for the most part.
In my experience, there are two types of overtime:
Overtime you put in because you want to - do not expect to be paid for this (unless you're a consultant, more on that later)
Mandatory overtime - if something has gone wrong, or a project is late, someone can sometimes tell you to put in some overtime. This should be paid for, and be aware that not all managers can demand mandatory overtime, this will vary from company to company.
There is nothing wrong with working a little bit extra from time to time - perhaps you're working on an interesting project, or you want to make a good impression - but unless you have an agreement with your employer, don't expect to be paid for this.
Working a little bit extra can be fun when you can choose when you want to do it.
However, if it is expected that you work overtime, all the time, this is a warning sign. It can work fine in the short term, but in the long term it can be very stressful, and you can risk burning out.
I would suggest talking (confidentially) to someone in the HR department, if that is an option.
We're not paid overtime like most companies.
I don't think it's that uncommon in the IT industry, but perhaps it depends on what kind of job you have. It wasn't until I started working as a consultant that I started getting paid for overtime, in the sense that there's a bonus that is related to how much I work.
When you're a consultant, being paid for overtime isn't such a big deal anymore - as you work more hours, the client is billed more hours, and thus it is not as expensive for the company you work for to pay you for overtime. It'll be more expensive for the client perhaps, but the nature of consulting is usually that you simply bill for hours spent. I've never heard of any consultants working for free.
Not sure why being paid for overtime is such a big deal, and I'm not sure how it is in other industries.