Immigration Site

I had my green card since sep 2007,I worked mayby 2 weeks before getting the card and mayby 2 weeks after receiving it,came back to my country for 3 months and then started my full time job.Problem is i didnt file tax from this 3-4 week job,dont know if the employed paid taxes for me.Since staring my job ( until now ) Ive always did my taxes and never was due.Dont know what to do,its been a few years.I ve also received form to get my voting card-filled it-sent it back and received my voting card,never voted and sent it back with a note that i didnt asked for it
Could it be a problem? I know that there is a question if i filed taxes every time and if i owe any taxes and if i got registred for voting.
Thanks for any responses

Ana

File an amended return for the year when you had the 3-4 week job, to add that income to your tax return.

Was that form a voter registration form? Did that form ask if you were a US citizen, or have a sentence declaring that you are a US citizen?

didnt state any,just asked to fill my name,address,so i wrongly assumed i can get a voting card

what if the employer didt pay taxes for me ?also i closed the account where i did deposit checks and dont remember the amounts ( less than 1500$ maximum ) is there any way to figure it out ? could it affect getting my citizenship?

another questions is was i eligible to work ? 2 weeks before getting my green card ? sorry,i know its a mess.What is amended return?