Hi DiogoBaptista98, ,
thanks for your feedback. If you are familiar with the OSM tools, you can just revert may change and fix your errors your own way. Anyhow I recommend to use JOSM capabilities and fix those errors before you upload them. May be you like to educate yourself about its internal validator:

https://wiki.openstreetmap.org/wiki/JOSM/Validator
Guido
