There's quite a lot so I'm going to go through your points in the order you mention them.
The lack of pay rise- were you expecting one? How do you feel this is unfair, did everyone else get one? Did you have any concerns about the client changes affecting your role?
Attendance. This sounds petty but actually it's pretty usual to be at work at least slightly before working hours start, and for management especially. If you start at 8.30 but don't walk in til 8.30 it's inevitably going to be a few minutes before you're actually working. As you are a manager I expect this concern is partly about setting an example. If managers aren't seen to be committed then its difficult to expect more junior staff to be. Is there any reason you can't get there 10 minutes earlier? How do you feel this is unfair, is everyone else allowed to wander in bang on 8.30 without comment?
Initiative. I actually think there is no way managers should sit waiting for work to be handed to them, so I think his comments are fair enough. How do you feel this is unfair?
Can't really answer the comments about not being able to work on a particular assignment without knowing what the commitments were and whether refusing assignments is generally acceptable at your work.
You ought to be able to go and see the GP. It's not clear whether they didn't let you go at all, or didn't let you take it out of your holiday. If the latter, can't see a problem. Again, how is this unfair, do others take hours of holiday entitlement or just days, and can others take it at very short notice but not you?
Firms policies about mobiles and lateness, can't see a problem. You may not like the policies but they are not unfair unless they are not universally applied.
In generally it sounds as though you are not happy with the concerns that have been raised, but unless there's more to it, it all sounds pretty fair enough.
What's not clear is whether any of this is either genuinely unfair, or related to your maternity leave. If other people are treated differently and/or you have reason to believe that your maternity leave is the reason (for example) you are expected to seek work rather than it be handed to you, then that's more of an issue.
In terms of having another baby, as you are late 30s I would suggest doing that as soon as possible, then the time you will be there will be limited.