Almost fainting after volume day squats, after adding carbs

[ElDemonio]

Background (trying to keep it short):

- Current stats: 176lb, 34yo, 5'10".
- Did the initial LP around 4-5 years ago. Real life gets in the way so have ran a few cycles of getting lifts up/taking a few weeks off/repeat. BW hovering around 176-190lb.

- At the start of this year, I started to follow a cleaner diet. Basically, during the week I focus on getting enough protein while cutting out carb portions (rice); most of my carbs come from residuals such as the crust in breaded chicken, grains in protein bars, snacks. Weekends are a bit more lax and I definitely get some sugars in, heh, so it's not really a strict low carb diet.
- After a few weeks off earlier this year, I ran LP again since May.
- After LP, I decided to start the Texas Method and try to get to a 405 squat. Starting BW before TM: 172.
- My current, fixed calorie intake from meals during TM is 2600/day. I add a couple protein bars (~520cal) on training days, plus a few random snacks during the week if I feel hungry; usually natural but calorie-dense ones, such as trail mixes, peanuts, almonds.
- Last week was week #9 of TM. Squats were 305x5x5, 335x5x1, challenging but I've felt worse during LP. Current body weight is 176.

To the point:
Today was volume day for week #10; sets 1-3 of 310x5 squats felt normal, but after finishing set #4 I got really light headed. Not the regular "slightly light headed after a heavy set of deadlifts", but more of a "had to get up and walk around while focusing on breathing and in not passing out".
I thought I probably rested too little or missed my breathing during the set, so I rested 10 minutes before the next one and focused on correct breathing during the set. Same feeling afterwards. Then I did some warmup sets for volume bench and started to feel the same way right before starting the work sets, so I decided to listen to my body and went home.
The squats themselves actually felt easier than on the previous 2 weeks, so it was not a matter of effort.

What I Changed:
The last two volume days started to feel a bit heavy, so I decided to start increasing calories by including carb portions back again this week. For today's mid day meal (~4 hours before lifting), I added brown rice (didn't measure it, around 3 handfuls).



Does this sound like something that can be caused by the increase in carbs? Given that the weights didn't feel extra-heavy and that I actually ate more, the only cause I can think of is some sudden change in blood sugar levels?

Thanks

[Karl Schudt]

Ok, there's one thing that jumps out at me.

- After LP, I decided to start the Texas Method and try to get to a 405 squat. Starting BW before TM: 172.

Quit doing Texas Method. Eat at least 3000 calories a day and do a genuine linear progression. You should not weigh 172lbs at 5'10" at the end of a linear progression.