I am in big trouble hope there is someone to help me here. I recently started to invest in cryptocurrencies but this week was hell for me. I made some mistakes that costed me big part of my portfolio.

First Ive sent some coins to Poloniex instead of my own wallet and they got lost since their support never replies.

Secondly which is much bigger trouble for me is; I was recently buying some LTC from Bittrex and wanted to send them to my Electrum. But somehow Electrum opened the inital wallet I have created during learning phase which is watch only wallet. I didnt notice it during transfer. I just noticed it and now I cant take my coins out. The wallet doesnt have password but I dont have the seeds. I saw in transactions that I used to sweep some coins from there to my real LTC account but since then I deleted all the info regarding watch only wallet when I was rearranging my password files.

I have at least the wallet addresss and wallet file. Can someone please help me how to get a private key from this address and save my coins. I really lost so much coins this week. I am already thinking leaving this crypto world.

Update 19.08:
Ok I just remember how I used to take coins out of that address. Litecoin core was the first crypto software I have downloaded and since downloading the block took so long I downloaded Electrum and got private key out of Core console and sweeped into the Electrum. But after sweeping I uninstalled the Core. Do you think is there anyway to see transaction history or sth like that on Electrum. Because I used private keys to sweep into Electrum before. But I havent saved that private key. Is there any chance Electrum saved this activity or log? Thanks.