Oddities in work of basic timer - 32L476GDISCOVERY

I'm writing library for HC-SR-4 (Ranging Module). To start measurement I have to:

1) send 10 us high signal to TRIGGER and than

2) measure duration of high signal on ECHO

To get 10 us duration I use one of basic timers with enabled interruption.

When I try to send signal TRIGGER for the first time I get strange early interruption. On the picture, you can see measurement performed by logical analyzer after pressing the button (which also sets high level on TRIGGER and starts timer):

Next press:

I can ignore this first interruption since after it timer works correctly. But to make library work I use two timers instead of one. For now it is not so bad but it is improper approach and I would like to understand why this happens.

Answering Clive:

Timer settings

/* TIM7 init function */
void MX_TIM7_Init(void)
{
 TIM_MasterConfigTypeDef sMasterConfig = {0};
 
 htim7.Instance = TIM7;
 htim7.Init.Prescaler = 79;
 htim7.Init.CounterMode = TIM_COUNTERMODE_UP;
 htim7.Init.Period = 9;
 htim7.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
 if (HAL_TIM_Base_Init(&htim7) != HAL_OK)
 {
 Error_Handler();
 }
 sMasterConfig.MasterOutputTrigger = TIM_TRGO_UPDATE;
 sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
 if (HAL_TIMEx_MasterConfigSynchronization(&htim7, &sMasterConfig) != HAL_OK)
 {
 Error_Handler();
 }
 
}

 Interruption

/**
 * @brief This function handles TIM7 global interrupt.
 */
void TIM7_IRQHandler(void)
{
 /* USER CODE BEGIN TIM7_IRQn 0 */
 
 /* USER CODE END TIM7_IRQn 0 */
 HAL_TIM_IRQHandler(&htim7);
 /* USER CODE BEGIN TIM7_IRQn 1 */
	HAL_TIM_Base_Stop_IT(&htim7);
	HAL_GPIO_TogglePin(TRIG_PORT, TRIG);
 /* USER CODE END TIM7_IRQn 1 */
}

 Button

void EXTI0_IRQHandler(void)
{
 /* USER CODE BEGIN EXTI0_IRQn 0 */
 
 /* USER CODE END EXTI0_IRQn 0 */
 HAL_GPIO_EXTI_IRQHandler(GPIO_PIN_0);
 /* USER CODE BEGIN EXTI0_IRQn 1 */
	HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_2);
	htim7.Instance->CNT = 0;
	HAL_TIM_Base_Start_IT(&htim7);
	HAL_GPIO_WritePin(TRIG_PORT, TRIG, 1);
	
 /* USER CODE END EXTI0_IRQn 1 */
}

 Clock configuration

Thank you,

Khetag