I'm allergic to something. one day my lip will swell up, next day my eyes. or i will have a verby bad skin rash that burns. but it comes and go.

? urticaria: For how long, and what seems to be the trigger, if any, take an antihistaminic as cetirizine on regular basis, whether you have the rash/swelling or not, don't drive if you become drowsy because of the medicine, if the lip swelling causes shortness of breath, you may want to keep an epinephrine pen handy, arrange to see an allergist or a dermatologist shortly,

Likely angioedema: sudden swelling, such as a lip doubling in size in less than an hour, or other part of the body--a fingertip, palm, tongue, penis, labia, eyelids--is an acute allergic reaction called angioedema. The chief danger is the larynx swelling up causing acute respiratory distress and if untreated, asphyxiation. It may be difficult to identify the trigger, such as jalapeños or NSAIDs.