hmm I thought this would literally translate to this - but I am not sure I can think of a context you could say such a thing? I guess you might have a regular doctor appointment of some kind! (I got it wrong as I put I am going on thursday)
I made the same mistake. I also put 'doctors' instead of doctor. But I think that's just because I colloquially say going to the doctors' even when I mean one doctor.
Yes, I'm a native English speaker and this sounds odd to me. Can't quite figure out what the precise diffrence is. 'I go to the doctors on Thursdays' suggests that you have a regular medical appointment with your doctor, at the doctor's surgery. 'I go to the doctor on Thursdays' - anyone could say this, when seeing the person who is a doctor, at their home or work, as part of their weekly routine. It could be a cleaner, fashion consultant, travelling chemist, anyone! But the point of the exercise is to learn Swedish, so I'm happy to have a phrase that helps me learn 'to the doctor' and 'on Thursdays'
It could also be "Each time I visit the doctor is on a Thursday." For the cleaner example to work, I would prefer doctor's, as the doctor himself/herself doesn't need to be present for the cleaning...
I don't understand the confusion, why it sounds odd, but I'm not a native English speaker. Apparently English people go to the doctors (=the building) but Swedish people go to the doctor (= the person). That is the same as in Dutch. BTW: "läkaren" is singular, "the doctor", and "läkarna" is "the doctors".