Side effects of tamoxifen

I had a breast cancer lump removed earlier in the year and had radiotherapy afterwards.  I also had Covid following the operation and suffered with fatigue during and afterwards.  I have been taking tamoxifen for 5 months and recently experienced some difficult side effects of strong dizziness, feeling very tired and very drowsy.  This resulted in me finding it difficult to even walk to the local park. 

I am having a break from the medication (6 weeks in total) and then trying again for a month in 2 weeks time.. My symptoms have eased but not completely.  Just wondered if anyone else had had similar experiences - guessing medication and Covid after effects could also be a factor.  Thank you.