Whatever feelings you experience, both good or bad are a direct result of how you interpret your thoughts. Remember thoughts create feeling, not the other way around, so you can do one of two things – you can ignore them (especially unhelpful thoughts) or you can listen to them and act. A thought is neutral until you give it meaning, so there is always an opportunity to use thought as a prompt to learn something and take action.
If for instance you are doing something most consider quite stressful like moving house, you can focus on all what can go wrong, get impatient when things move along too slowly or you can focus on positive thoughts about new beginnings and what positive action you can take to move things along or even choose to allow things to unfold at whatever pace it takes. Whether you fret and worry or take a more positive laid back stance, things will still work out the same.
Some of our thoughts are not worth entertaining and are best ignored and they will soon be replaced by something else. Some thoughts can actually be helpful in prompting you to take action to off set future problems.
Ultimately the point is to allow your thoughts to help you rather than allowing them to undermine or sabotage you in any way. Every negative thought has a flip side to a more positive and helpful thought depending on how you choose to see things. If you cannot find a positive then leave the thoughts alone by focusing on something else until more helpful thoughts pop in.