I'm out of my thyroid medicine (levothyroxine) and it been a week that i didn't take them, is there any side effects?

Nothing sudden: Over time you will simply have more & more vague signs on hypothyroidism. Fatigue, increased sensitivity to cold, constipation, dry skin, puffy face, hoarseness, heavier cycles, depressed mood, impaired memory and more. These will accumulate and amplify over time but can be avoided if you just renew your medicine. You take it for life.