Under stress and sometimes forgetting how to spell certain words or forget what i was doing for a few seconds,forget what i was saying if interrupted?

Forget me not: There can be many reasons for cognitive issues you describe. Certainly stress resulting in extreme anxiety or depression can impact the ability to recall information and the flow of thought processes. Learning disorders can do the same. Various medical conditions can present as memory problems. Medication side effects can impact thinking. Recommend seeing your doctor for a complete evaluation.