Concern About Prayer Validity and Modest Clothing Choices

Assalamu alaikum everyone. I began wearing the hijab a month ago, and I've been trying to dress more modestly, but it's hard to update my whole wardrobe at once. I found that men's shirts often fit more loosely and cover better, so I bought one that goes down to my thighs or knees. It has a pattern, but it doesn't look particularly masculine-I could ask some sisters for their opinion. I've also got some full-sleeved shirts that are just patterned, and for other tops, I use detachable sleeves over half-sleeve shirts. When I pray, I always wear an abaya that reaches my shins. My worry is: is it okay to wear shirts from the men's section just because they're baggier? The women's options I saw seemed less modest. I also bought a longer skirt to help, but it's just one for now. I know pants aren't ideal, but that's mostly what I have until I can get more skirts. With the abaya and hijab covering everything properly, could my prayers still be invalid due to these clothes? It's been on my mind and making me anxious. JazakAllah khair for any advice.