Isolated TWICE due to Covid and now boss is giving light threats?

Ok – so more of a vent but welcome advise if I am wrong. Since January 2020, I have been working two jobs. I work a full time (clinic admin.) and a part time (supermarket). I asked my part time job to reduce my hours to minimal so I can have 1 day off on the weekend. I was told this would take action at the end of January. Of course – this did not happen when I approached my manager a few times and she made excuses. Now, at my other job, I work at a clinic so still deal with patients. We had an encounter with a Covid-19 patient in March so isolated two weeks (entitled to do this). I got paid.

Last Friday, I had a high temperature so I had 2 G.PS check me out at work and they said to go home and take a test. Thus, I called sick on my weekend job. My store manager does not like me (he’s not the nicest) because I usually respond to his stupid comments instead of agreeing or being a yes man. He said I can come in if I feel well, I said I will call 111 and see what they say… Of course, 111 said stay at home. So, I called back and relayed this. He said he’s putting it as sick on my file but I can come in if I feel well…

I get a call from my department manager (supermarket) arguing that I have had time off etc, so they will put it as sick. I spoke to my union rep. and she said this is wrong – she did the EXACT same thing and no one said anything to her so not sure why they are pinpointing me. It even says on our staff website that this shouldn’t go on my record and to not come in.

So, I got a text from my manager (supermarket) again yesterday night in regards to study leave and time away from the company to focus on my postgrad. degree. She sent a passive aggressive test saying that I have had too much time off from the company and it’s better to take a study leave for 3 months plus… and ‘even then, your employment may get suspended.’ I find this a light threat. I have taken 8 days in total unpaid (with permission) and always got my shifts covered way in advance when I am exhausted and need a day off. So, I am not sure why she is bringing this up. I have had colleagues do similar things.

According to my union rep. they do these things to people they dislike, as in try and make it stressful and difficult. I am unfazed usually but now it’s starting to piss me off. I have a plan for when I get back to work (in a fortnight) but I am seriously ready to rip into all of these managers there. I am a MASSIVELY hard worker, just don’t take B.S. if something is wrong, I point it out. I clocked up about 60 hours a week in overtime last Christmas. But I am starting to lose it with their behaviour.