Salam , when ending Salah in Tasleem , in the second one I felt like it came out wrong (the pronunciation) caused maybe by my tongue getting in the way or my mouth made another sound I’m not really sure , I just didn’t want to repeat it because of waswas , if I do sujud sahw is that fine.
Also when pronouncing siratal latheena, because I’ve been trying to perfect my letter pronunciation, I’ve been told the “t” is heavy “tt-uh” .i feel like the h comes out well and it sounds like Sirat-hal latheena, does it invalidate my Salat because I have extreme was was and sometimes I repeat an Ayah of Fatiha more than 5 times and I don’t like going back to repeat it .
Another question is ghayril maghdubi, I know the a in ghayril is pronounced more like Ghoyril If you don’t pronounce it exactly like that is it valid , I’ve also been suffering with proununcing ghaynun and sometimes when I get it right It may not come out as ghoyril rather it comes at ghayril and I don’t want to go back and say it again cause then I’ll be repeating it a lot and waswas might come in , I’m trying my best to perfect my recitation because I’m not arabic and some of these letters were taught to me in a different accent and now it’s hard for me to adjust .
I’ve been going through a hard time with this waswas , it’s eating me up more and more everyday, I’m broken , I need help , I pray to Allah everyday for help and I know I’m not meant to get angry when it happens a lot but I do and it’s upsetting me because I’m only human and I’m trying my best . My prayers lasted maximum 8 minutes before now they end in 10 mins minimum and sometimes reaches 15 because I keep repeating that ghaynun and it’s so hard for me because I can’t pronounce it well , please I need help , this is really damaging me . Also when saying tasleem If you doubt that you’ve made a mistake can you repeat it again for example in your final one (left side ) you feel like you mispronounced it so you said it again and did sujud sahw,

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, is His slave and Messenger.

The remedy for the Waswaas you are suffering from is to completely ignore it and not pay any attention to it at all, as giving free reign to Waswaas leads to enormous evil consequences. So recite Al-Faatihah once, and do not repeat any of its verses more than once. No matter how much Waswaas you may experience about mispronouncing the Taa’ (ط), Ghayn (غ), or any other letter, ignore it, and do not repeat the recitation. The same applies to Tasleem; recite it once, and do not repeat it no matter how much Satan whispers to you that you mispronounced it, and do not perform Sujood Sahw (prostration of forgetfulness). This is the optimal remedy for the Waswaas you are suffering from. We ask Allah to bless you with recovery and wellness.

Allah Knows best.